How do I remove a virus?

Get the basics on computer viruses: Part 3

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What does it mean?

antivirus software (AV)
A computer program designed to detect and respond to malicious software, such as viruses and worms.

update (noun)
A broadly released fix for a specific problem addressing a noncritical, non-security-related bug.

virus definition
Also known as a virus signature. A recognized pattern of unique computer code contained in a virus.

Even for an expert, removing a virus properly from a system is often a daunting task without the help of specific tools designed for the job. Some viruses and other unwanted software (including spyware) are even designed to reinstall themselves after they have been detected and removed! Fortunately, through updating your computer and using free, trial-period, or low-cost antivirus tools offered by many companies, you can permanently remove unwanted software and help prevent future infection.

To help remove a virus:

1. Use our free virus scanner (for Microsoft Windows XP, Windows 2003, or Windows 2000 users). To use it, go to the Protection Center and click Protection Scan.
Note: This tool does not prevent viruses from infecting your system; instead, it looks for existing viruses on your PC and then works to remove any it finds.

2. Visit Microsoft Update and install the latest updates.

3. If you currently use antivirus software, visit the manufacturer's Web site, update your antivirus software, and then perform a thorough scan of your system. If you don't currently use antivirus software, subscribe to a service such as Windows Live OneCare and scan your system immediately.

Why didn't my antivirus software work?

If you already have antivirus software installed on your system, it's very important to keep it current with the latest updates (called virus definition or virus signature files) that help the tool identify and remove the latest threats. In addition, not all antivirus tools are created equal; if you find that the one you use isn't finding viruses, consider doing some research to find an alternative.

How do I install updates if I can't use my computer?

In some cases, you might find yourself in a catch-22 where you might be unable to download antivirus tools or update your system because a virus has already disabled your computer. In this case, use another computer to download the tools to a disk, or call toll-free (866) PCSAFETY (727-2338) for additional help.