What do you do when Windows starts misbehaving? (I mean, after you've pounded on your desk and yelled at the computer?) The range of things that can go wrong with Windows is truly staggering--from sudden lock-ups, freezing, and crashing, to gobbledygook error messages, to the dreaded Blue Screen of Death.

When confronted with a Windows problem, most people just start poking around in dialog boxes, more or less at random, hoping that they'll get lucky and stumble on the fix. There's a much more effective strategy, however--a methodical approach to problem-solving that usually helps you find and fix the overwhelming majority of Windows woes, including system crashes. I've listed eight steps you can take to troubleshoot any Windows problem. Go through this checklist, one item at a time, and you have an excellent chance at finding and fixing any Windows problem.

If your system was working fine last week but is having problems this week, try to identify everything that's changed recently. Have you installed any new hardware or software? Did you update a device driver? Try uninstalling the software, removing the hardware device, or restoring the old driver temporarily, to see if the problem goes away. If you can reproduce the problem with specific steps, you've got a much better chance of knowing when you've found the fix.

If you're using Windows 98, Windows Millennium Edition, or Windows 2000, the built-in Help system includes several wizards that can walk you through troubleshooting basics, step by step. Click the Start button and choose Help. At the bottom of the Contents pane, select the Troubleshooting entry to expand it, and then scroll through the list of Windows Troubleshooters until you find the one that's right for your situation. If you're using Windows 95, use Microsoft's online troubleshooters.

I once dragged a harried support professional to my office to fix a printer problem. He fished around behind the computer and discovered, to my chagrin, that the cable had come undone. Before you spend too much time troubleshooting, check all the obvious hardware connections. Make sure your power is working. Check to see that every cable is securely connected. Restart the device and see if that fixes the problem.

Running out of free disk space can cause all sorts of odd symptoms. To check free disk space, open the My Computer window, right-click on the icon for your C: drive, and choose Properties. Run the ScanDisk and Defrag utilities to verify that your disk is OK.

Viruses can cause the most bewildering problems of all. Use a good antivirus program--preferably from a write-protected bootable floppy disk--to scan for viruses. Need a good antivirus program? Try my collection of Virus Protection links.

Restart your computer, and when you see the "Starting Windows" prompt, press F8. Select Safe Mode at the menu. This starts Windows up in a special diagnostic mode that loads only drivers and Windows components that are absolutely required. If your system runs OK in Safe Mode, you can bet that the problem is with a third-party program or driver. If your system still has problems, you may have a hardware problem, or you may need to reinstall Windows.

Believe it or not, one of the most common causes of system crashes is a poorly written video driver. You can quickly discover whether this is the case by replacing your video driver with one of Windows' generic video drivers. The Windows 98 System Configuration Utility can help you do this job automatically. Or you can do it yourself by following these steps: Open Control Panel's Display option and click the Settings tab. On the Adapter tab, you'll see the name of your current video driver. Click the Change button to its right to start the Update Device Driver Wizard. Choose either the Standard Display Adapter (VGA) or Super VGA options and restart your system. If this cures the problem, contact the maker of your video adapter for a new driver.

Some software programs run automatically at startup, without appearing in the taskbar. To troubleshoot this sort of problem, use the Windows 98 System Configuration Utility to shut down all automatically starting programs; if that cures the problem, start adding programs back one at a time until you find the guilty party.