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A+™ Certification : Operating Systems

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3. Diagnosing, and Troubleshooting

3.1 Recognize and interpret the meaning of common error codes and startup messages from the boot sequence, and identify steps to correct the problems.

  • Common Error Messages and Codes

    • Boot failure and errors

      • Invalid boot disk

      • Inaccessible boot device

      • Missing NTLDR

      • Bad or missing Command interpreter

    • Startup messages

      • Error in CONFIG.SYS line XX

      • Himem.sys not loaded

      • Missing or corrupt Himem.sys

      • Device/Service has failed to start

    • A device referenced in SYSTEM.INI, WIN.INI, Registry is not found

    • Event Viewer – Event log is full

    • Failure to start GUI

    • Windows Protection Error

    • User-modified settings cause improper operation at startup

    • Registry corruption


  • Using the correct Utilities

    • Dr. Watson

    • Boot Disk

    • Event Viewer

3.2 Recognize when to use common diagnostic utilities and tools. Given a diagnostic scenario involving one of these utilities or tools, select the appropriate steps needed to resolve the problem.
Utilities and tools may include the following:

  • Startup disks

    • Required files for a boot disk

    • Boot disk with CD-ROM support

  • Startup Modes

    • Safe mode

    • Safe Mode with command prompt

    • Safe mode with networking

    • Step-by-Step/Single step mode

    • Automatic skip driver (ASD.exe)

  • Diagnostic tools, utilities and resources

    • User/installation manuals

    • Internet/web resources

    • Training materials

    • Task Manager

    • Dr. Watson

    • Boot Disk

    • Event Viewer

    • Device Manager

    • WinMSD

    • MSD

    • Recovery CD


  • Eliciting problem symptoms from customers

  • Having customer reproduce error as part of the diagnostic process

  • Identifying recent changes to the computer environment from the user

3.3 Recognize common operational and usability problems and determine how to resolve them.
Content may include the following:

  • Troubleshooting Windows-specific printing problems

    • Print spool is stalled

    • Incorrect/incompatible driver for print

    • Incorrect parameter

  • Other Common problems

    • General Protection Faults

    • Bluescreen error (BSOD)

    • Illegal operation

    • Invalid working directory

    • System lock up

    • Option (Sound card, modem, input device) or will not function

    • Application will not start or load

    • Cannot log on to network (option – NIC not functioning)

    • Applications don’t install

    • Network connection

  • Viruses and virus types

    • What they are

    • TSR (Terminate Stay Resident) programs and virus

    • Sources (floppy, emails, etc.)

    • How to determine presence

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