TECHNICAL-SUPPORT EXPERTS say that most problems they encounter with Windows computers could have been averted if the owners had only avoided these four common mistakes:

1. Not installing anti-virus software. Increasingly sophisticated viruses and other forms of malware can slow your computer to a crawl.

2. Installing anti-virus software. In its never-ending battle with viruses and other forms of malware, increasingly sophisticated anti-virus software can slow your computer to a crawl.

3. Connecting to the Internet. It may be true that the Internet, for other computers, is a wonderland of information and entertainment; but for a Windows computer a more apt comparison would be to a minefield.

4. Pushing the power button. Technical-support experts agree that almost every problem with any Windows computer can be traced back to turning the computer on. Your computer should be stored in a cool, dry place, free from dust, mold, or users.