Step 4: Install Anti-malware Programs

Mucho Importante: uninstall any old anti-malware program(s) that have similar functions before upgrading or replacing them with a new one. Don't say I didn't warn you. ;-)

Notes

The term "Malware" includes "Spyware".
Set a "System Restore" point before you use anti-malware software to remove any "parasites". You may remove something that you find out later you shouldn't have.
Beware of bogus anti-spyware programs. Some of them install their own spyware -- some of it much worse than ordinary spyware.
Mucho Importante: Most anti-malware programs use "signatures" (definitions) to look for matches to any malware on your computer. New malware is created every day. You need updated signatures to keep up. The program itself may occasionally need an update too. There is often a way to check for updates online, right from the program. Turning on "automatic updates" for each program is the best way to keep them everything up to date.
It won't do any good to make your home computer bullet proof if you then use public PCs, like the ones in Internet Cafes or Public Libraries, to do business online. They are very likely to have spyware installed. Guess where your information goes -- right to fraudsters who know how to use it to clone your identity for their own use. [more]

[Basic] spyware/malware protection

First, install SP3 for Windows XP. It adds some good early-warning protection. That is, if you actually pay attention to the warnings that will pop-up. Don't let your normal reaction to ordinary pop-ups make you click a choice too quickly.

VIPRE, by Sunbelt Software, is my personal antivirus choice. It's fast, accurate, easy on system resources, and inexpensive to boot. [review] VIPRE combines antivirus and antispyware protection. And their support people are all located in Tampa Bay, Florida. ;-) [other recommendations]

The tutorials at bleepingcomputer.com are a good way to learn about installing and using anti-malware programs. They'll give you a good idea of what's involved.

Anti-malware programs can be quite confusing the first time you use them. Don't let that stop you. Use the program's Help file, get someone to help you, or get more information at our spyware/malware removal page.

[Strong] spyware/malware protection

For the ultimate protection, run your computer in a Limited account -- not an Administrator account. This will neutralize most current and future threats, because Limited accounts do not allow program installation. That means malware can't install itself either.

[Robust] spyware/malware protection

Add intrusion prevention software (HIPS). Microsoft AntiSpyware is good in that role, but DefenseWall HIPS, Prevx Pro or BlackICE will add a layer of powerful protection. I use Online Armor, which combines intrusion prevention and a robust firewall.