4. Step 3 - System-specific Diagnostic Tools and Techniques

4.1. Windows 95/98 System Troubleshooting

The Windows 95/98 onscreen help system (accessed via Start->Help->Contents->Troubleshooting) has a interactive troubleshooting section covering some of the most common problems.

Chapter 35 of the Windows 95 Resource Kit, and Chapter 27 of the Windows 98 Resource Kit also give a good introduction to Windows troubleshooting. Information on these and other resources are included below in Step 4.

Some of the most common causes of Windows 95/98 problems are:
  • Insufficient resources

    - insufficient memory (RAM) or free disk space can cause some software problems. If an application runs fine on its own, or when processing small documents, but misbehaves when running at the same time as another program, or when handling large documents, then this could be your problem. Another symptom of insufficient memory, is a high level of disk activity all the time you are using the machine. The solutions are to add more RAM to your system and/or to do some disk "housekeeping" to try and free up disk space. The Resource Meter (accessed via Start->Programs->Accessories->System Tools) can be used to monitor various aspects of your system's memory usage.

  • Faults in Specific Software Modules

    - these may often be remedied by installing a relevant update or "service pack" from Microsoft or other software manufacturer.

  • General Protection Failures (GPFs)

    - occur when Windows encounters a problem it cannot handle in an orderly way. Insufficient resources and faults in software modules are common causes of GPFs.

  • Problems with Device-drivers and Configurations

    - each hardware device connected to your machine has a software device driver to control it. Device drivers are installed and configured via the appropriate Windows control panel. On "Plug-and-Play" systems, Windows will automatically and detect Plug-and-Play devices. However, with older systems or devices which are not Plug-and-Play, some manual configuration of the device may be required. Alternatively, a device-driver may have problems which can only be cured by obtaining an updated version from the manufacturer.

Windows Safe Mode If a serious Windows problem occurs, such as a badly misconfigured device, you may need to use Windows safe mode. This runs Windows in a mode where device drivers are not activated and therefore cannot misbehave. Sometimes in such situations, Windows automatically starts up in safe mode. If it doesn't, you can request this - press the <F8> key as soon as you see the "Starting Windows" message during system startup; you should be presented with the system's Boot Menu which should include at least the following options:
  • Normal
  • Logged (Bootlog.txt)
  • Safe Mode
  • Step-by-Step Confirmation
  • Command Prompt
  • Safe Mode Command Prompt Only
Choose the Safe Mode option to run Windows in safe mode. There are occasions on which you might also wish to use the Command Prompt option - this takes you to an MSDOS-type command prompt.

In safe mode, you can use the various Windows Control panels to add, remove, re-install or re-configure device drivers via the Windows Control panels. If you restart the system in its normal mode, use the Device Manager section of the System Control panel to check the status of any device.


The ScanDisk utility included with Windows 95/98 is a powerful disk-fixing utility. If Windows is closed down improperly, ScanDisk normally runs automatically. However, you can also run it by starting up your system in Command Prompt mode (see previous section) and typing the command SCANDISK at the command prompt.

4.2. Apple Macintosh System Troubleshooting

The Macintosh onscreen help system (accessed via the Troubleshooting topic on the ? or Help menus) has a interactive troubleshooting section covering some of the most common problems.

The most common errors on Macintosh systems are Finder Errors, Bus Errors, and Bombs. Common causes of these are:
  • Corrupt/outdated Application Software

    - Bombs and Finder Errors can be caused by a corrupted application program one of its associated files. This is the likely cause if these errors have started to occur only when using the same piece of software. If this happens a reinstallation of the software in question will often fix the problem. However, a good starting place BEFORE reinstalling the system is to remove any preference files for the application from the System Folder/Preferences folder. Sometimes, older versions of an application will not work with a new machine or system software version. In this case, an updated version of the application will be needed.

  • System Extension Conflicts

    - If the errors do not seem to be linked to a particular application, or occur during system start-up, then it is possible that two or more system extensions are conflicting. In version 7.5 and later of the system software, this can be tested by using the Extensions Manager Control Panel. By saving the current (non-working) set of extensions and then turning off the loading of different extensions until the problem disappears, it should be possible to deduce the extension that is causing the problem.

  • If your system does not start up correctly you can switch off all the extensions by holding down the <Shift> key during the initial startup process - you should see a message Extensions Off on the Welcome to Macintosh startup screen. If the machine starts correctly without the extensions then you can use the process above to turn on extensions selectively until the problem starts again.

If you find you are experiencing a number of errors it may be worth reinstalling your system software - but before doing so try removing the Finder Preferences file. A fresh 'clean' set of preferences will be generated on startup and this can help in resolving system problems.

Handy Keys for Troubleshooting

Here are some key combinations which may be useful when troubleshooting Macintosh Problems

  • Switching Off Extensions on Startup

    - To prevent extensions loading on startup hold down the <Shift> key while the system starts up. You should see a message "Extensions Off" as the system starts up. This can aid in troubleshooting problems caused by extension conflicts.

  • Rebuilding the Desktop

    - To rebuild the Macintosh's hidden Desktop file, hold down <Option> and <Command> keys (these are also sometimes labelled the <Alt> or the <Apple> key) while the machine goes through its startup sequence. Near the end of the startup sequence, you should eventually get a message asking you if you want to  rebuild the desktop file for the startup hard-disk (to rebuild a floppy disc desktop hold down the keys as you insert the disk). Rebuilding the Desktop can eliminate problems with corrupt icons and devices (such as CD-ROMs floppy discs etc.) not mounting correctly.

  • Zapping the P-RAM

    - To zap the P-RAM (Parameter RAM) hold down together the <Option> , <Command> , <P> and <R>keys and restart the system - release all the keys when the system restarts itself a second time. This clears the contents of the P-RAM which holds the current date/time, monitor type and other hardware / device details. If a machine is behaving erratically and software problems have been eliminated then zapping the P-RAM, forcing the system to refresh its settings may help. Note that you will need to correct the Date and Time using the Date/Time Control Panel after zapping the P-RAM. The P-RAM contents are maintained by a small battery. If your machine keeps forgetting its date/time setting, this battery may need replacing.

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