If you own a personal computer, chances are that it runs
some version of Microsoft® Windows®.
While the ideas used here are mostly applicable to Windows XP®, many of them are useful with other Microsoft® operating systems.
The items below go from most important to least important.
You don't have to do them all at once -- start with the first item to get started with some protection, add the 2nd item for more, etc.
When Microsoft® creates a new patch for their operating system, I've heard that virus writers around the world race to understand that patch & the security problem that the patch fixes. Then, they write viruses or other malware (bad software) which uses that security problem to gain access to other computers. The best way you can protect yourself is to keep your operating system and applications (i.e. Microsoft Word®, Excel®, etc.) up-to-date with the latest patches.
One way to do this is to go to Microsoft® Windows® Update every Wednesday or Thursday. Start Internet Explorer, then use the menu pick across the top of the screen to go to Tools > Windows Update. Follow any instructions on download new software, then keep returning to Windows Update until the Express and Custom buttons are on your screen.
Choose as many of the Critical updates as the screen will let you choose, then press Review and Install Updates, then Install Updates.
Often, after you do one update, you'll need to reboot and/or return to Windows Update page to check for others. When no High Priority (=Critical) updates are left, you may wish to consider doing other updates -- but it's important to make sure that you have the critical updates installed.
Once you are updating on a regular basis, I suggest purchasing Norton or McAfee Antivirus. I've used (and dislike) them both, but feel that the Antivirus protection is important. At least once a week, update your virus protection and scan your system.
The Antivirus software has just recently begun working against adware & spyware. Some great (and some free/some not free) anti-adware/anti-spyware utilities are next on the list:
Other good antispyware programs exist; these are just a few that I've used & liked.
Recently, a new kind of virus called a rootkit has appeared. Rootkits may allow other Internet users to use your machine time, send junk email (like viruses) or capture your logins & passwords (like spyware). The interesting thing about rootkits are that they are very hard to detect and -- in some cases -- remove from your system. Specifically, none of the anti-virus, anti-adware or anti-spyware tools above detected a rootkit that I had on my system for several months. I suggest using:
to find the rootkits. Not everything printed by RootkitRevealer is a problem; some things are just normal changes that happened while running the software. I can't tell you how to remove rootkits because I've only had experience with one specific one, and I had to try several things before I was finally able to remove it.