Illegal Operations Checklist

The first thing to check is whether the hard disk is full. To do so you can use one of two methods

  • In 9x, NT or 2000, double click My Computer. Right click the C: drive and click Properties. You'll see a graphic of how much free space you have.
  • In a DOS prompt, type DIR [ENTER]. Ignore what flies by, and just remember how many "bytes free" it tells you at the end.

    • If your hard drive has less than about 50 or 100 megabytes free space then your programs may be unable to properly cache their data to the hard drive, even if you've got gobs of free space on a D: or other drive

    If you haven't run SCANDISK and DEFRAG within the last month it may be worth a try. If you run SCANDISK and find errors, fix them and run SCANDISK again. It should find no errors the second time around. If it does, you've got a hard drive that can't hold critical data and needs to be replaced.

    One of the main reasons Windows has been so historically unstable is that it is a memory-intensive operating system that unfortunately came out in an age when large amounts of memory were not affordable. Since now this is no longer the case, the third thing to try is to install enough memory to bring the memory in the machine up to at least 64 meg and 128 meg if possible. Why is this important? It is important because whenever Windows runs out of physical memory it uses VIRTUAL memory which means hard disk space.

    If you start getting a lot of random problems that you didn't get before and you've ruled out the first three things, your hard drive may be getting old and unreliable. Consider a replacement.

    Try fixes that may be available for the offending application [e.g. clearing the cache in Netscape]

    Try uninstalling and reinstalling the offending application(s), or just ones you no longer use. To uninstall an application FIRST BACK UP ANY DATA THE APPLICATION USES, and then try in order the following:

  • If the program comes with an Uninstall program (you'll see it in the folder for the program), run the uninstaller that ships with the program
  • The second choice is through the Control Panel. Go to Start | Settings | Control Panel | Add Remove Programs. Find out if your application is listed. If it is then highlight the program entry and click on Add/Remove

    • In either case you MIGHT be asked the question about whether to remove shared files and directories. ALWAYS ANSWER NO. they might be in use by other programs.
  • Manual uninstall -- this involves deleting the directory that the program is installed on and then deleting the appropriate registry keys. Before doing so, back up all data that is important, and / or the registry, because foulups will require one of two things -- restoration of the registry from a backup OR reinstallation of the operating system. Also contact the program vendor to find out which registry keys should be deleted. The safest thing is to email the program vendor first. Then you can proceed with full instructions at hand.

    Lastly the problem MIGHT be that an application has tampered with critical operating system files (DLL files) that Windows needs. In Windows-98 the problem can be solved by running System File Checker when Windows is first installed. Then when problems occur in the future, it can be rerun with the "Check for altered files" option. For 95, certain updates might have to be removed through the control panel. The subject of DLL files will be covered more thoroughly in future updates of this site.

    For Windows 95 always consider whether version conflicts may be the reason for your problems. This is commonly caused by borrowing someone else's Windows-95 CDROM because you've lost your own (or perhaps because you bought the system from someone who preinstalled Windows for you but didn't give you a CDROM). This is especially a issue for version conflicts between versios dating on or before 12-31-95 and those on or after 8-24-96. If this is indeed the problem, the only reliable remedy is to reinstall the operating system cleanly.

    Consider the option of "One operating system for yourself (to get your work done) and another one for the kids". I would NOT recommend this if your problems have been solved already by the addition of more RAM or hard drive capacity. What operating systems to consider -- I think in today's world that will be primarily either Windows-2000 or Linux, or even both.