Recent Changes - Search:

Welcome to CAVI, the Cisco Academy for the Vision Impaired.

Course Fees Linux Wiki HTML Wiki Documentation Index PmWiki FAQ

Edit SideBar

Main /

Chapter 12 - Advanced Troubleshooting

12.0 Advanced Troubleshooting

12.0.1 Introduction >12.0.1.1 Introduction

The image on this page shows an IT technician replacing the laptop WI-FI card and laptop memory RAM module.

12.1 Computer Components and Peripherals

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >112.1.1.1 Six Steps for Advanced Troubleshooting Computer Components and Peripherals

Figure 1 on this page shows the following table listing the first step in troubleshooting computer components and peripherals problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • What type of computer do you have?
  • What is the brand and the model of the computer?
  • Can you describe what happens when the computer boots?
  • How often does the computer fail to start?
  • What is the first screen you see when you turn on the computer?
  • What sound does the computer make as it starts?
Close-ended Questions
  • Has anyone done any repair work on the computer recently?
  • Has anyone else used the computer?
  • Is any media installed in a floppy or optical drive?
  • Does the computer have a USB drive attached?
  • Can the computer be used to connect to a wireless network?
  • Is the computer secured in a locker room at night?
  • Do you have Windows installation media available?

Figure 2 on this page shows the following table listing the second step in troubleshooting computer components and peripherals problems:

Step 2: Establish a Theory of Probable Cause
Common causes of security problems.
  • Computer power problems
  • Computer power problems
  • Loose external cable connection
  • Loose data cable connection
  • Loose adapter card
  • Faulty RAM
  • Incorrect device driver
  • Fans are Dirty
  • Incorrect jumper settings
  • CMOS battery problem
  • Incorrect firmware
  • Failed parts

Figure 3 on this page shows the following table listing the third step in troubleshooting computer components and peripherals problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Restart the computer
  • Disconnect and reconnect the external cables
  • Disconnect and reconnect the internal cables
  • Secure the adapter card
  • Roll back or reinstall the device driver
  • Replace the RAM
  • Clean the fans
  • Reset the jumpers
  • Secure or replace the CMOS battery
  • Update the firmware
  • Listen for beeps
  • Look for error codes or messages

Figure 4 on this page shows the following table listing the fourth step in troubleshooting security problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting security problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot the computer
  • Restart external devices
  • Access all drivers and shared resources
  • Print a document
  • Read and write to all storage devices
  • Validate the amount of RAM, the CPU, speed, and the date and time
  • Test network connectivity
  • Execute commonly used applications

Figure 6 on this page shows the following table listing the sixth step in troubleshooting security problems:

Step 6: Document Findings, Actions, and Outcomes
Document your Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.2 Common Problems and Solutions for Components and Peripherals

The figure on this page shows the following table listing the common problems and solutions for components and peripherals.

Problem Symptom Probable Causes Possible Solutions
An "OS not found" error message is displayed when the computer is started.
  • The hard drive has failed.
  • The hard drive is not jumpered correctly.
  • The boot order is not set correctly in BIOS.
  • The MBR is Corrupted.
  • Replace the hard drive.
  • Change the jumper settings on the hard drive.
  • Change the boot order in BIOS to boot the correct hard drive.
  • Boot the computer to the Recovery Console. At the command prompt, use the bootrec /fixmbr or bootrec /fixboot in windows 7 or vista or the fixmbr command in windows xp.
RAID cannot be found
  • Cables connected to the hard drives are connected incorrectly.
  • The external RAID controller is not receiving power.
  • The RAID controller has failed.
  • The BIOS settings are incorrect.
  • Examine all the cable connections to all of the drives in the array.
  • Check the power connection to the raid controller.
  • Replace the RAID controller.
  • Reconfigure the BIOS settings for the RAID controller.
RAID stops working
  • The external RAID controller is not receiving power.
  • The RAID controller has failed.
  • The BIOS settings are incorrect.
  • Check the power connection to the RAID controller.
  • Replace the RAID controller.
  • Reconfigure the BIOS settings for the RAID controller.
A computer exhibits slow performance.
  • The computer does not have enough RAM.
  • The computer is running to many programs.
  • The hard drive is full.
  • Install additional RAM.
  • Close unneeded programs.
  • Run Disk cleanup or replace the hard drive with a larger capacity hard drive.
The Computer Does not Recognise a SCSI drive.
  • The SCSI Drive has an incorrect SCSI ID.
  • SCSI termination is not set correctly.
  • The external SCSI drive was not powered on prior to booting the computer.
  • Reconfigure the SCSI ID.
  • Ensure that the SCSI chain is terminated at the correct end points.
  • Turn on the drive before booting the computer.
The computer does not recognize a removable external drive.
  • The OS Does not have the correct drivers for the removable external drive.
  • The USB port has too many attached devices to supply adequate power.
  • Download the correct drivers for the drive.
  • Attach external power to the device or remove some of the USB devices.
After updating the CMOS firmware, the computer will not start. The CMOS firmware update did not install correctly.
  • Restore the original firmware from the onboard backup if there is one available.
  • Contact the motherboard manufacturer to obtain a new CMOS chip.
  • If the motherboard has two CMOS chips, the second CMOS chip can be used.
The computer reboots without warning, locks up, or displays error message or the BSOD
  • The front side bus is set too high.
  • The CPU Multiplier is set too high.
  • The CPU voltage is set too high
  • Reset to factory default settings for the motherboard.
  • Lower the FSB settings.
  • Lower the Multiplier settings.
  • Lower the CPU voltage settings.
After upgrading from a single core CPU to a dual core CPU, the computer runs more slowly and only shows one CPU graph in the Task Manager. The BIOS does not recognise the dual core CPU. Update the BIOS firmware to support the dual core CPU.

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.3 Apply Troubleshooting Skills to Computer Components and Peripherals

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.4 Lab - Repair Boot Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.5 Lab -

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.6 Lab - Troubleshooting Hardware Problems in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.7 Lab - Troubleshooting Hardware Problems in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.1.1 Applying Troubleshooting Process to Computer Components and Peripherals >12.1.1.8 Lab - Troubleshooting Hardware Problems in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.2 Operating Systems

12.2.1 Applying Troubleshooting Process to Operating Systems >112.1.1.1 Six Steps for Advanced Troubleshooting Operating Systems

Figure 1 on this page shows the following table listing the first step in troubleshooting operating system problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • What operating system is installed on the computer?
  • What programs have been installed recently?
  • What programs have been installed recently?
  • What updates or service packs have been installed?
  • What error messages have you received?
  • What were you doing when the problem was discovered?
Close-ended Questions
  • Does anyone else have this problem?
  • Have you changed your password recently?
  • Have you made any changes to your computer?
  • Does anyone else have access to your computer?
  • Has this problem happened before?

Figure 2 on this page shows the following table listing the second step in troubleshooting operating system problems:

Step 2: Establish a Theory of Probable Cause
Common causes of operating system problems.
  • Corrupted or missing systems files
  • Incorrect device driver
  • Failed update or service pack installation
  • Failed update or service pack installation
  • Corrupted registry
  • Failing or faulty hard drive
  • Incorrect password
  • Virus infection
  • Spyware

Figure 3 on this page shows the following table listing the third step in troubleshooting operating system problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Reboot the computer
  • Examine the event Logs
  • Run sfc/scannow
  • Roll back or reinstall the device driver
  • Unistall recent updates or service packs
  • Run system restore
  • Run CHKDSK
  • Log in as a different user
  • Boot to the last known good configuration
  • Run a virus scan
  • Run a spyware scan

Figure 4 on this page shows the following table listing the fourth step in troubleshooting operating system problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting operating system problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot the computer
  • Access all drives and shared resources
  • Check event logs to ensure there are no new warnings or errors
  • Check device manager to ensure there are no warnings or errors
  • Make sure applications run properly
  • Make sure the internet can be accessed
  • Check task manager to ensure that there are no unidentified programs running

Figure 6 on this page shows the following table listing the sixth step in troubleshooting operating system problems:

Step 6: Document Findings, Actions, and Outcomes
Document Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.2.1 Applying Troubleshooting Process to Operating Systems >12.2.1.2 Common Problems and Solutions for Operating Systems

The figure on this page shows the following table listing the common problems and solutions for operating systems.

Problem Symptom Probable Causes Possible Solutions
The computer displays an “invalid Boot Disk” error after the POST.
  • Media that does not have an operating system is in a drive.
  • The boot order is not set correctly in BIOS.
  • The hard drive is not detected or the jumpers are not set correctly.
  • The hard drive does not an operating system installed.
  • The MBR is corrupted.
  • The computer has a boot sector virus.
  • The hard drive failing.
  • Remove all media from the drivers.
  • Change the boot order in BIOS to start with the boot drive.
  • Reconnect the hard drive cables or reset the hard drive jumpers.
  • Install an operating system.
  • Use bootrec /fixmbr command from system recovery options of Windows 7 or Vista.
  • Run fdisk /mbr from the CLI in windows XP only.
  • Run virus removal software.
  • Replace the Hard drive.
The computer displays an “Inaccessible Boot Device” error after the POST.
  • Recently installed device driver is incompatible with the boot controller.
  • BOOTMGR is corrupted in Windows 7 or windows Vista.
  • NTLDR is corrupted in windows XP.
  • Use last known good configuration to boot the computer.
  • Boot the computer in safe mode and load a restore point from before the installation of new hardware.
  • Restore the BOOTMGR file from Windows 7 or windows vista installation media.
  • Restore the NTLDR from windows XP installation media.
The computer displays a “BOOTMGR is missing” error after the POST in Windows 7 and Windows Vista
  • BOOTMGR is missing or damaged.
  • Boot Configuration Data is missing or damaged.
  • The boot order is not set correctly in BIOS.
  • The MBR is corrupted.
  • The hard drive is failing.
  • The hard drive jumpers are not set correctly.
  • Restore BOOTMGR from installation media.
  • Restore the Boot Configuration Data from installation media.
  • Change the boot order in BIOS to start with the boot drive.
  • Run chkdsk /F /R from the recovery console.
The computer displays a “Missing NTLDR” error after the POST in windows XP
  • NTLDR is missing or damaged.
  • Ntdetect.com is missing or damaged.
  • Boot.ini is missing or damaged.
  • The boot order is not set correctly in BIOS.
  • The MBR is corrupted.
  • The hard drive is failing.
  • The hard drive jumpers are not set correctly.
  • Restore NTLDR from installation media.
  • Restore ntdetect.com from installation media.
  • Restore boot.ini from installation media.
  • Change the boot order in BIOS to start with the boot drive.
  • Run fdisk /mbr from the cmd line prompt.
  • Run chkdsk /F /R from the recovery console.
  • Reset the hard drive jumpers.
A service failed to start when the computer booted.
  • The service is not enabled.
  • The service is set to manual.
  • The failed service requires another service to be enabled.
  • Enable the service.
  • Set the service to Automatic.
  • Re-enable or re-install the required service.
A device did not start when the computer booted.
  • The external device is not powered on.
  • The data cable or power cable is not connected to the device.
  • The device has been disabled in BIOS.
  • he device has failed.
  • The device has a conflict with a new installed device.
  • The driver is corrupted.
  • The driver is still being installed
  • Power on the external device.
  • Secure the data cable and power cable to the device.
  • Enable the device in the BIOS.
  • Replace the device.
  • Remove the newly installed device.
  • Re-install or roll back the driver.
A program listed in the registry is not found.
  • One or more program files have been deleted.
  • The uninstall program did not work correctly.
  • The installation directory has been removed.
  • The hard drive has become corrupted.
  • The computer has a virus.
  • Re-install the program.
  • Re-install the program and run the un-install program again.
  • Run chkdsk /F /R to fix the hard drive file entries.
  • Scan for and remove the virus.
The computer continually restarts without displaying the desktop.
  • The computer is set to restart when there is a failure.
  • A start-up file has become corrupted.
  • Press F8 to open the advanced Options Menu and choose Disable automatic restart on system failure.
  • Run chkdsk /F /R from the recovery console.
The computer displays a black or blue screen of death (BSOD).
  • A driver is not compatible with the hardware.
  • The RAM is failing.
  • The power supply is failing.
  • The CPU is failing.
  • The motherboard is failing.
  • Research the STOP error and the name of the module that produced the error.
  • Replace any failing devices with known good devices.
The computer locks up without any error messages.
  • The CPU or FSB settings are incorrect on the motherboard or in the BIOS settings.
  • The computer is overheating.
  • An update has corrupted the operating system.
  • The RAM is failing.
  • The hard drive is failing.
  • The power supply is failing
  • Check and reset the CPU and FSB settings.
  • Check and replace any cooling devices as necessary.
  • Uninstall the software update or perform a System Restore.
  • Run chkdsk /F /R from the recovery console.
  • Replace any failing devices with known good devices.
  • Scan for and remove the virus.
An application does not install
  • The downloaded application installer contains a virus and has been prevented from installing by virus protection software.
  • The installation disk or file is corrupted.
  • The install application is not compatible with the operating system.
  • There are too many programs running and not enough memory remaining to install the application.
  • The hardware does not meet the minimum requirements.
  • The security warning was ignored or cancelled.
  • Obtain a new installation disk or delete the file and download the installation file again.
  • Run the installation application under compatibility mode.
  • Close applications before installing a new program.
  • Install hardware that meets minimum installation requirements.
  • Run the installation again and accept the security warning.
A computer with windows 7 installed does not run Aero. The computer does not meet the minimum hardware requirements for running Aero. Upgrade the processor, RAM, and video card to meet minimum Microsoft requirements for running Aero.
The search feature takes a long time to find results.
  • The index service is not running.
  • The index service is not indexing in the correct locations.
  • Start the index service using service.msc.
  • Change the settings of the index service in the advanced options panel.
The UAC no longer prompts the user for permission. The UAC has been turned off. Turn on the UAC in the user account applet in the Control Panel.
No gadgets appear on the desktop.
  • The gadgets have never been installed or have been uninstalled.
  • The XML necessary to render the gadget is broken, corrupted, or not installed.
  • Right click on the desktop > Gadgets > right click on a gadget > add.
  • Register the file msxml3.dll by entering regsvr32 msxml3.dll > enter the command prompt.
The computer is running slowly and has a delayed response.
  • A process is using most of the CPU resources.
  • The hardware does not meet the requirements to run Aero
  • Restart the process with services.msc.
  • If the process is not needed, end the process with task manager.
  • Restart the computer.
  • Disable Aero.
The OS is missing.
  • Partition is not set as active.
  • Missing startup files for windows.
  • Set the active partition using the diskpart tool from the system recovery options.
  • Run windows Startup Repair.
When you run a program, a missing or corrupt DDL message is displayed.
  • One or more programs using the DLL file was uninstalled and removed the DDL file that was needed by another program.
  • The DLL file was not registered.
  • The DLL file was corrupted during bad installation.
  • Reinstall the program that has missing or corrupt DLL file.
  • Reinstall the application that uninstalled the DLL.
  • Register the DLL file using Regsvr32 command.
  • Run sfc /scannow in Safe Mode.
RAID is not detected during installation
  • Windows 7 does not include the proper drivers to recognize RAID.
  • RAID settings in BIOS are incorrect.
  • Install the proper drivers.
  • Change settings in BIOS to enable RAID.
A system file is corrupted. Computer was shut down improperly.
  • Repair your computer from the advanced startup options menu.
  • Boot computer in safe mode and run sfc/scannow
GUI is missing for all users or GUI fails to load.
  • Missing startup files for Windows.
  • Windows updates have corrupted the operating system.
  • Repair your computer from the advanced startup options menu.
  • Run windows startup repair.
  • Reinstall the OS.
The computer shuts down without warning. A program is causing the windows OS to shut down unexpectedly. Boot to Safe Mode and manage startup applications using the msconfig command line utility.
Computer boots to safe mode.
  • A program has been installed that causes the computer to boot in safe mode.
  • The computer has been configured to boot in safe mode.
  • Use msconfig to adjust the startup settings for the program.
  • Use msconfig to configure the computer to boot normally.
Computer boots only to VGA mode Corrupt video driver. Reinstall the video driver.

12.2.1 Applying Troubleshooting Process to Operating Systems >12.2.1.3 Apply Troubleshooting Skills to Operating Systems

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.2.1 Apply Troubleshooting Process to Operating Systems >12.2.1.4 Lab - Fix an Operating System Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.2.1 Apply Troubleshooting Process to Operating Systems >12.2.1.5 Lab - Remote Technician - Fix an Operating System Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.2.1 Apply Troubleshooting Process to Operating Systems >12.2.1.6 Lab - Troubleshooting Operating System Problems in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.2.1 Apply Troubleshooting Process to Operating Systems >12.2.1.7 Lab - Troubleshooting Operating System Problems in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.2.1 Apply Troubleshooting Process to Operating Systems >12.2.1.8 Lab - Troubleshooting Operating Systems in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.3 Networks

12.3.1 Applying Troubleshooting Process to Networks >112.1.1.1 Six Steps for Advanced Troubleshooting Networks

Figure 1 on this page shows the following table listing the first step in troubleshooting network problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • When did the problem start?
  • Which network LEDs are lit?
  • What problems are you experiencing?
  • Is there anything else you can tell me about the problem?
  • What other users are having problems?
  • Can you describe your network configuration?
Close-ended Questions
  • Has any network equipment changed?
  • Has any peripherals been added to your computer?
  • Have any other computer been added to the network?
  • Have you rebooted your computer

Figure 2 on this page shows the following table listing the second step in troubleshooting network problems:

Step 2: Establish a Theory of Probable Cause
Common causes of network problems.
  • Incorrect IP information
  • Incorrect wireless configuration
  • Disable Network connection
  • Verify the wireless router configuration
  • Verify cabling and connections
  • Verify network equipment settings

Figure 3 on this page shows the following table listing the third step in troubleshooting network problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Restart the network equipment
  • Renew IP address
  • Reconnect all of the network cables
  • Verify the wireless router configuration
  • Ping the local host
  • Ping default gateway
  • Ping an external website
  • Verify the network equipment settings

Figure 4 on this page shows the following table listing the fourth step in troubleshooting network problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting network problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot all of the network equipment
  • Reboot any computer that experienced network problems
  • Validate all LEDs on the network equipment
  • Use ipconfig /all command to display IP addressing information for all network adapters
  • Use the ping command to check network connectivity to an external website
  • Use nslookup command to query your DNS server
  • Use the net view command to show the available shared resources on a network
  • Print to a shared printer

Figure 6 on this page shows the following table listing the sixth step in troubleshooting network problems:

Step 6: Document Findings, Actions, and Outcomes
Document your Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.2 Common Problems and Solutions for Networks

Figure 1 on this page shows the following table listing the common problems and solutions for network connection problems:

Problem Symptom Probable Causes Possible Solutions
A computer can connect to a network device by the IP address but not by the host name.
  • Incorrect host name.
  • Incorrect DNS settings.
  • DNS server is not operational
  • Re enter the host Name.
  • Re enter the IP address of the DNS server.
  • Reboot the DNS server.
The computer does not obtain or renew the IP address.
  • The computer is using a static IP address.
  • Loose network cable.
  • Firewall is blocking DHCP
  • Enable the computer to obtain an IP address automatically.
  • Check the cable connections.
  • Change the firewall settings to allow DHCP traffic.
An IP address conflict message displays when connecting a new computer to the network The same IP address is assigned to two different devices on the network. Configure each device with a unique IP address.
A computer has network access but does not have internet access.
  • The gateway IP address is incorrect.
  • A router is not configured incorrectly
Reboot the router and reconfigure the router settings.
The computer automatically obtained the IP address 169.254.x.x but cannot connect to the network.
  • The DCHP server is not on.
  • The computer cannot communicate with the DHCP server.
  • Another computer has been assigned a static IP address that has been assigned from the DHCP pool.
  • Turn on the DHCP server.
  • Run ipconfig /release and then ipconfig /renew.
  • Reboot the computer
Users are experiencing slow transfer speeds on the wireless network.
  • Wireless security has not been implemented allowing unauthorized user access.
  • There are too many users connected to the access point.
  • Implement a wireless security plan.
  • Add another access point
Users are experiencing intermittent connectivity on the wireless network
  • Users is too far away from access point.
  • The wireless signal is experiencing interference from outside sources.
  • There are too many users connected to the access point
  • Ensure the access point is centrally located.
  • Change the channels on the wireless network.
  • Add another access point.

Figure 2 on this page shows the following table listing the common problems and solutions for network email failures:

Problem Symptom Probable Causes Possible Solutions
The computer cannot send or receive email.
  • The computer has incorrect email client settings.
  • The email server is down.
  • There is a loose or disconnected network cable.
  • Reconfigure the email client settings.
  • Reboot the email server or notify your email service provider.
The computer can send email, but cannot receive email. The inbox is full Archive or delete emails to create space.
The computer cannot receive a certain email attachment.
  • The email attachment is too large.
  • The email attachment contains a virus and has been blocked by virus protection.
  • Ask the sender to split the attachment into smaller parts and resend them in individual emails.
  • Ask the sender to scan the attachment before sending it.
The computer cannot authenticate to the email server. The email server settings are incorrect. Enter the correct email server settings.

Figure 3 on this page shows the following table listing the common problems and solutions for FTP and secure Internet connection problems:

Problem Symptom Probable Causes Possible Solutions
A user cannot access the FTP server.
  • Port forwarding is not enabled in the router.
  • The maximum number of users has been reached.
  • Enable port forwarding on the router to forward port 21 to the IP address of the FTP server.
  • Increase the maximum number of simultaneous FTP users on the FTP server.
The FTP client software cannot find the FTP server
  • The FTP client has an incorrect IP address or port settings.
  • The FTP server is not running
  • Enter the correct IP address and port settings in the FTP client.
  • Reboot the FTP server.
The FTP server disconnects the client after a short period of inactivity The FTP server does not allow connected clients to remain connected when no commands are being sent to the FTP server. Increase the amount of time an FTP client is allowed to remain connected without performing any actions.
A computer cannot access a specific HTTPS site. The browser certificate SSL setting is incorrect.
  • Clear the SSL state.
  • Add the trusted root certificate.
  • Select>tools>internet options>Advanced tab and ensure the SSL checkbox is enabled.

Figure 4 on this page shows the following table listing the common problems and solutions when using network troubleshooting tools:

Problem Symptom Probable Causes Possible Solutions
Computer can ping an IP address but not a host name.
  • The host name is incorrect.
  • The DNS settings of the computer are incorrect.
  • The DNS server is not operational.
  • NetBIOS over TCP/IP is not enabled.
  • Enter the correct host name.
  • Enter the correct DNS settings.
  • Reboot the DNS server.
  • Enable NetBios over TCP/IP.
A computer on one network cannot ping a computer on another network.
  • There is a bad connection or broken device between the two networks.
  • ICMP echo requests is disabled
  • Use tracert to locate which link is down and fix the broken link.
  • Ensure that the ICMP echo request is enabled.
Nslookup reports “can’t find server name for address 127.0.0.0: timed out”.
  • The DNS IP address is not configured on the local computer.
  • The DNS IP address is not correct.
Add the IP address of a valid DNS server to the TCP/IP properties of the LAN adapter.
A computer cannot connect to a shared network folder using the net use command.
  • The folder is not shared.
  • The computer is not in the same workgroup.
  • Make sure the network folder is shared using the net share command.
  • Set the computer to the same workgroup as the computer with the shared network folder.
When attempting to use the ipconfig /release or ipconfig /renew command, you receive the message: “No operation can be performed on the adapter while its media is disconnected
  • The network cable is unplugged.
  • The computer has been configured with a static IP address.
  • Reconnect the network cable.
  • Change the TCP/IP properties of the LAN adapter to use DHCP.
The computer cannot telnet into a remote computer.
  • The telnet service has stopped.
  • The remote computer has not been configured to accept telnet connections.
  • Start the telnet service on the remote computer.
  • Configure the remote computer to accept telnet connections.
The network icon in the notification area shows a yellow exclamation point.
When attempting to use the ipconfig /release or ipconfig /renew command, you receive the message: the operation failed as no adapter is in the state permissible for this operation. 		A static IP address has been assigned to the interface. Change the configuration from a static IP address to obtain an IP address automatically.

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.3 Apply Troubleshooting Skills to Networks

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.4 Lab - Fix a Network Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.5 Lab - Remote Technician - Fix a Network Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.6 Lab - Troubleshooting Network Problems in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.7 Lab - Troubleshooting Network Problems in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.3.1 Applying Troubleshooting Process to Networks >12.3.1.8 Lab - Troubleshooting Network Problems in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.4 Laptops

12.4.1 Applying Troubleshooting Laptops >12.4.1.1 Six Steps for Advanced Troubleshooting Laptops

Figure 1 on this page shows the following table listing the first step in troubleshooting laptop problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • In what environment are you using the laptop?
  • When did the problem start?
  • What problems are you experiencing?
  • What happens when the laptop boots?
  • What can you see on your screen?
  • Is there anything else you can tell me about the problem?
Close-ended Questions
  • Has anyone done any repair work on the laptop recently?
  • Has anyone else used the laptop?
  • Does the laptop connect to the internet?
  • Is there a wireless NIC in the laptop?
  • Have you ever had any problems like this before?

Figure 2 on this page shows the following table listing the second step in troubleshooting laptop problems:

Step 2: Establish a Theory of Probable Cause
Common causes of laptop problems.
  • Laptop battery does not have a charge
  • Laptop battery will not charge
  • Loose cable connection
  • The inverter does not work
  • External keyboard does not work
  • Num lock is on
  • Loose RAM
  • A Fn key has disabled a capability
  • A button or slide switch has disabled the wireless connection

Figure 3 on this page shows the following table listing the third step in troubleshooting laptop problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Use AC power instead of battery
  • Replace AC adapter
  • Remove and reinsert the battery
  • Replace battery
  • Check BIOS settings
  • Disconnect and reconnect cables one at a time
  • Verify Num Lock is off
  • Reinstall RAM
  • Reboot the laptop

Figure 4 on this page shows the following table listing the fourth step in troubleshooting laptop problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting laptop problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot the computer
  • Attach all peripherals
  • Operate Laptop using only battery
  • Print a document from an application
  • Type sample document to test keyboard
  • Check event viewer for warnings or errors

Figure 6 on this page shows the following table listing the sixth step in troubleshooting laptop problems:

Step 6: Document Findings, Actions, and Outcomes
Document your Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.4.1 Applying Troubleshooting Process to Laptops>12.4.1.2 Common Problems and Solutions for Laptops

Figure 1 on this page shows the following table listing the common problems and solutions for laptop displays:

Problem Symptom Probable Causes Possible Solutions
The laptop screen appears black or very dim. A buzzing noise may also be heard. Laptop display screen inverter or backlight lamp failure.
  • Replace the display inverter.
  • Replace the backlight lamp.
The laptop screen only displays vertical lines that can change colours. Laptop display screen failure. Replace the laptop display screen
External laptop display connected to the laptop shows content but the laptop screen is blank. The laptop screen is not set to display output. Press the Fn key with the appropriate multifunction key to display output on the laptop screen
Laptop display screen and external monitor will not display images while the laptop hard drive and fans are operating normally. The laptop motherboard or the video card has failed.
  • Replace the laptop motherboard if it has onboard video.
  • Replace the video card.
The laptop does not return from Standby or Hibernate mode. The laptop has a conflict between the BIOS settings and the windows power management settings. Reconfigure the laptop BIOS settings and the windows power management settings.

Figure 2 on this page shows the following table listing the common problems and solutions for laptop storage devices and RAM:

Problem Symptom Probable Causes Possible Solutions
The laptop hard drive has data access errors and makes unusual noises Hard drive has failed Replace the hard drive
The laptop will not boot or access a newly installed hard drive.
  • The hard drive is not connected properly.
  • The BIOS does not recognize the new hard drive
  • Reconnect the hard drive.
  • Update the laptop BIOS.
The laptop accesses the hard drive excessively
  • The virtual memory is set incorrectly.
  • Additional RAM is needed.
  • Free hard drive space is limited.
  • Change the virtual memory settings.
  • Install additional RAM.
  • Delete or remove unneeded files and applications.
The laptop makes a long beeping noise after installing new RAM
  • The wrong type of RAM is installed.
  • The RAM is installed incorrectly.
  • A damaged RAM module is installed.
  • Install the correct type of RAM.
  • Remove and reinstall the RAM.
  • Replace the damaged RAM module.

Figure 3 on this page shows the following table listing the common problems and solutions for laptops power and input devices problems:

Problem Symptom Probable Causes Possible Solutions
The laptop LED power light is not on when the laptop is plugged into an AC outlet.
  • The AC power source is not working.
  • The power cable is not securely connected to the laptop.
  • The AC adapter is defective.
  • Plug the laptop into a known good power source.
  • Unplug and securely connect the power cable to the laptop.
  • Replace the AC adapter.
The laptop will not power on when only using the battery.
  • The battery is not connected correctly.
  • The battery does not have a charge.
  • The battery is defective.
  • Remove and reconnect the battery.
  • charge the battery.
  • Replace the battery
The laptop operation time while using the battery is very short. The battery is old Replace the battery
Date and time are incorrect when the laptop is powered on.
  • The CMOS battery has failed.
  • The CMOS battery is loose.
  • Replace the CMOS battery.
  • Remove and reinstall the CMOS battery
The laptop touch pad or pointer device is not responsive
  • The touch pad or pointer device is disabled.
  • The touch pad or pointer device is defective.
  • Enable the pointer device from the control panel.
  • Replace the pointer device.
  • Use a mouse as the new pointer device.
The laptop keyboard does not work or individual keys do not work.
  • The keyboard has been damaged by liquid.
  • The laptop keyboard has a loose connection.
  • The keyboard is worn or old.
  • Clean the keyboard.
  • Reconnect the laptop keyboard.
  • Replace the laptop keyboard.
  • Use an external keyboard.

Figure 4 on this page shows the following table listing more laptop problems and solutions:

Problem Symptom Probable Causes Possible Solutions
The laptop shuts off randomly or is excessively hot.
  • The laptop has poor ventilation.
  • The laptop has a faulty fan.
  • The CPU heat sink is dirty or loose.
  • Clean all of the vents.
  • Replace any faulty fans
  • Clean and reseat the heat sink.
The laptop will not start up and only the fans and LEDs are working. The CPU has failed. Replace the CPU.
The laptops built in speakers are not producing any sound.
  • The audio is disabled in BIOS.
  • The sound is muted.
  • The laptop built in speakers are damaged.
  • Enable the audio in BIOS.
  • Un-mute the sound.
  • Replace the speakers.
  • Use external speakers.
Cannot insert a PC card into the laptop.
  • The pc card is not supported by the laptop.
  • The plastic protector is installed in the card slot.
  • Replace the PC card with an ExpressCard.
  • Remove the plastic protector from the card slot.
  • Purchase a PC card to expressCard adapter.

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.3 Apply Troubleshooting Skills to Laptops

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.4 Lab - Fix a Laptop Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.5 Lab - Remote Technician - Fix a Laptop Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.6 Lab - Troubleshooting Laptop Problems in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.7 Lab - Troubleshooting Laptop Problems in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.4.1 Applying Troubleshooting Process to Laptops >12.4.1.8 Lab - Troubleshooting Laptop Problems in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.5 Printers

12.5.1 Applying Troubleshooting Process to Printers >112.5.1.1 Six Steps for Advanced Troubleshooting Printers

Figure 1 on this page shows the following table listing the first step in troubleshooting printer problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • What type of printer do you have?
  • What is the brand and model of your printer?
  • What type of paper are you using?
  • What problems are you experiencing with your printer?
  • What software or hardware has been changed recently on your computer?
  • What were you doing when the problem was identified?
  • What error messages have you received?
Close-ended Questions
  • Is the printer under warranty?
  • Can you print a test page?
  • Is this a new printer?
  • Is the printer powered on?
  • Does the problem appear on every page?
  • Has the paper been changed recently?
  • Is the a problem with only this printer?
  • Does the problem occur when you use the other applications?
  • Is your printer connected to the network wirelessly?

Figure 2 on this page shows the following table listing the second step in troubleshooting printer problems:

Step 2: Establish a Theory of Probable Cause
Common causes of printer problems.
  • Loose cable connections
  • Paper Jams
  • Equipment power
  • Low ink warning
  • Out of paper
  • Errors on equipment display
  • Errors on computer screen
  • Empty toner cartridge
  • Print server is not working
  • The printer cannot establish a connection to the wireless network

Figure 3 on this page shows the following table listing the third step in troubleshooting printer problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Restart the printer
  • Disconnect and reconnect the cables
  • Restart the computer
  • Check the printer for paper jams
  • Reseat the paper in the paper trays
  • Open and close the printer tray
  • Ensure printer doors are closed
  • Clear the jobs in the printer queue
  • Restart the printer pooler service
  • Reinstall the printer software
  • Remove the packing tape from the inkjet cartridge nozzle arm
  • Restart printer server
  • Reconfigure the wireless settings of the printer

Figure 4 on this page shows the following table listing the fourth step in troubleshooting printer problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting printer problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot the computer
  • Reboot the printer
  • Print a test page from the printer control panel
  • Print a document from an application
  • Reprint the customer's problem document

Figure 6 on this page shows the following table listing the sixth step in troubleshooting printer problems:

Step 6: Document Findings, Actions, and Outcomes
Document your Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.2 Common Problems and Solutions for Printers

The figure on this page shows the following table listing the common problems and solutions for printer problems:

Problem Symptom Probable Causes Possible Solutions
Printer prints unknown characters.
  • The printer may be plugged into a UPS.
  • A incorrect print driver installed.
  • The printer cables are loose.
  • The printer has been set to pause printing.
  • The printer has been set to Use Printer offline.
  • Plug the printer directly into the wall outlet.
  • Uninstall the incorrect print driver and install the correct printer driver.
  • Secure the printer cables.
  • Set the printer to use printer online.
Paper jams when printing.
  • Wrong paper type is being used.
  • Humidity causes the paper to stick together.
  • Replace the paper with the manufacturer recommended paper type.
  • Insert new paper in the paper tray.
Printer will not print large or complex images. The printer does not have enough memory Add more memory to the printer.
Laser printer prints vertical lines or streaks on every page. The drum is damaged
  • Replace the drum or replace the toner cartridge when it contains the drum.
  • Remove and shake the toner cartridge.
Printed pages show ghost images.
  • The drum is scratched or dirty.
  • The Drum wiper blade is worn.
Replace the drum or replace the toner cartridge when it contains the drum.
The toner is not fusing to the paper. The fuser is defective Replace the fuser
Paper is creased after printing The pickup rollers are obstructed, damaged or dirty. Clean or replace the pickup rollers
Paper is not being fed into the printer The pickup rollers are obstructed, damaged or dirty. Clean or replace the pickup rollers
Each time a network printer is restarted, users receive a "Document failed to print" message.
  • Printer's IP configuration set for DHCP.
  • A device on the network has the same IP address as the network printer.
  • Assign a static IP address to the printer.
  • Assign a different static IP address to the printer.

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.3 Apply Troubleshooting Skills to Printers

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.4 Lab - Fix a Printer Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.5 Lab - Remote Technician - Fix a Printer Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.6 Lab - Troubleshooting Printer Problems in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.7 Lab - Troubleshooting Printer Problems in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.5.1 Applying Troubleshooting Process to Printers >12.5.1.8 Lab - Troubleshooting Printer Problems in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.6 Security

12.6.1 Applying Troubleshooting Process to Security>112.6.1.1 Six Steps for Advanced Troubleshooting Security

Figure 1 on this page shows the following table listing the first step in troubleshooting security problems:

Step 1: Identify the Problem
Open-Ended Questions.
  • What problems are you experiencing?
  • When did the problem start?
  • How are you connected to the internet?
  • What type of firewall or you using?
  • What security software is installed on your computer?
  • What network resources can you access using wireless?
  • What resource permissions do you have?
Close-ended Questions
  • Do you have a firewall?
  • Has anyone else used your computer?
  • Is your security software up to date?
  • Have you scanned you computer recently for viruses?
  • Have you ever had this problem before?
  • Have you changed password recently?
  • Have you received any error messages on your computer?
  • Have you shared your password?
  • Do you have permissions for the resouce?

Figure 2 on this page shows the following table listing the second step in troubleshooting security problems:

Step 2: Establish a Theory of Probable Cause
Common causes of security problems.
  • The user account is disabled
  • The user is using an incorrect username or password
  • The user does not have the correct folder or file permissions
  • The firewall configurations are incorrect
  • The user's computer has been infected by a virus
  • The wireless security configurations are incorrect on the client
  • The security configurations are incorrect on the wireless access point

Figure 3 on this page shows the following table listing the third step in troubleshooting computer security problems:

Step 3: Test the Theory to Determine Cause
Common steps to determine cause.
  • Verify the user's account settings
  • Reset the user's password
  • Verify the user's permissions for folders and files
  • Check firewall logs for errors
  • Verify the firewall settings
  • Scan and remove viruses from the computer
  • Verify the wireless security configuration of the client
  • Verify the security configuration on the wireless access point

Figure 4 on this page shows the following table listing the fourth step in troubleshooting security problems:

Step 4: Establish a Plan of Action to Resolve the Problem and Implement the Solution
If no solution is achieved in the previous step, further research is needed to implement the solution.
  • Helpdesk Repair Logs
  • Other Technicians
  • Manufacturer FAQs
  • Technical Websites
  • Newsgroups
  • Computer Manuals
  • Device Manuals
  • Online Forums
  • Internet Search

Figure 5 on this page shows the following table listing the fifth step in troubleshooting security problems:

Step 5: Verify Full System Functionality and if Applicable Implement Preventative Measures
Verify Solution and Full System Functionality
  • Reboot the computer
  • Log on to the computer
  • Connect to the network using wireless
  • Verify file and folder access
  • Verify that no virus is found with a virus scan

Figure 6 on this page shows the following table listing the sixth step in troubleshooting security problems:

Step 6: Document Findings, Actions, and Outcomes
Document your Findings
  • Discuss the solution implemented with the customer
  • Have the customer verify the problem has been solved
  • Provide the customer with all paperwork
  • Document the steps taken to solve the problem in the work order and the technician’s journal
  • Document any components used in the repair
  • Document the time spend to resolve the problem

12.6.1 Applying Troubleshooting Process to Security >12.6.1.2 Common Problems and Solutions for Security

Figure 1 on this page shows the following table listing the common problems and solutions for malware problems:

Problem Symptom Probable Causes Possible Solutions
Message "MBR has been changed or modified" appears at boot up. A boot sector virus has changed the master boot record. Boot the computer with a bootable media and run antivirus software to remove the boot sector virus.
A windows 7 or windows vista computer starts with the error message "Error Loading Operating System". A virus has damaged the master boot record
  • Boot the computer from the installation media.
  • At the install windows screen, select Repair your computer.
  • At the command prompt, type bootrec.exe /fixmbr.
A windows 7 or windows vista computer starts with the error message "Caution: this hard disk may be infected by virus!". A virus has damaged the master boot record
  • Boot the computer from the installation media.
  • At the install windows screen, select Repair your computer.
  • At the command prompt, type bootrec.exe /fixboot.
A windows XP computer will not start A virus has damaged the master boot record
  • Boot the computer from the Windows XP installation disc or media.
  • At the startup screen, select R-Recovery Console.
  • At the command prompt, use the fixmbr command.
A windows 7 computer will not boot. A virus damaged windows system files
  • Boot the computer from a windows PE media.
  • Access windows startup repair tool to recover corrupted system files.
Your contacts are receiving spam from your email account. Your email account has been hijacked by a virus or spyware.
  • Run antivirus software and repair, delete, or quarantine the infected files.
  • Run antispyware software and remove any spyware infections.
  • After the computer is cleaned, change the email account password.

Figure 2 on this page shows the following table listing the common problems and solutions for user permissions problems:

Problem Symptom Probable Causes Possible Solutions
User can log on but receives an "access denied" message when trying to access some folders and files. The user is not a member of the group that has access to the folders and files.
  • Add the user to the correct group.
  • Add the correct user's permissions to the folders and files.
User can locate a file on the server but cannot download the file. The user permissions are not correct. Change the user's permission on the file to read and execute.
User is gaining access to a subfolder that should be inaccessible. The subfolder inherited permissions from the upper level folder. Change the subfolder permission settings so it does not inherit the permissions from the parent folder. Set the proper permissions for the subfolder.
Users of a group cannot see one folder to which they are supposed to have access. The folder permissions are set to deny. Change the folder permissions to allow.
Encrypted files that are moved over the network to a new computer are no longer encrypted. The new computer does not have an NTFS partition. Convert the partition on the new computer to NTFS and re-encrypt the files.

Figure 3 on this page shows the following table listing the common problems and solutions for computer security settings problems:

Problem Symptom Probable Causes Possible Solutions
Computer runs slowly at the same time every day. Antivirus software is set to scan the computer at the same time every day. Configure the antivirus software to scan the computer when the computer is not in use.
User complains that the computer BIOS settings keep changing The BIOS password is not set, allowing others to change the BIOS settings. Set a password to protect access to the BIOS settings.
TPM does not show up in Device Manager. The TPM is disabled Enable the TPM in the BIOS

Figure 4 on this page shows the following table listing the common problems and solutions for firewall or proxy settings problems:

Problem Symptom Probable Causes Possible Solutions
Computer cannot ping another computer on the network
  • The windows firewall is blocking ping requests.
  • A router is blocking ping requests.
  • Configure windows firewall to allow ping requests.
  • Configure the router to allow ping requests.
Laptop firewall exceptions are allowing unauthorized connections from rogue computers.
  • The windows firewall settings are incorrect.
  • The windows firewall is disabled.
  • Set the windows firewall to "do not allow exceptions when using a public network".
  • Enable the windows firewall.
Computer cannot telnet to another computer.
  • The windows block port 23 by default.
  • The router is blocking port 23.
  • Configure the windows firewall to open port 23.
  • Configure the router to allow port 23
Email program is properly configured but cannot connect to the email server.
  • The email server is down.
  • Windows firewall is blocking the email software
  • Verify that the email server is operational.
  • Create a windows firewall exception for your email software.
Computer can ping outside the local network but has no internet activity.
  • The windows firewall is blocking port 80.
  • The router is blocking port 80
  • Configure windows firewall to open port 80.
  • Configure the router to allow port 80
Computer can ping proxy server, but has no internet connectivity.
  • The browser proxy server settings are incorrect.
  • The proxy server is offline.
  • Re-enter the proxy server settings, including the IP address and port of the proxy server, and any exceptions that should be defined.
  • Reboot the proxy server.

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.3 Apply Troubleshooting Skills to Security

The image on this page shows a number of help desk staff wearing headsets and sitting at computers.

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.4 Lab - Fix a Security Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.5 Lab - Remote Technician - Fix a Security Problem

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.6 Lab - Troubleshooting Access Security in Windows 7

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.7 Lab - Troubleshooting Access Security in Windows Vista

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.6.1 Applying Troubleshooting Process to Printers >12.6.1.8 Lab - Troubleshooting Access Security in Windows XP

See IT Essentials 5.0 Labs and Worksheets Accessible Files

12.7 Advanced Troubleshooting

12.7.1 Summary12.7.1.1Summary

The image on this page shows an IT technician replacing the laptop WI-FI card and laptop memory RAM module.

End of Chapter 12: Advanced Troubleshooting.

This is the end of the IT Essentials course chapter diagram descriptions.

Edit - History - Print - Recent Changes - Search
Page last modified on March 26, 2015, at 01:00 PM