At some point on April 1, the Conficker virus, which has quietly infected millions of PCs worldwide to herd them into a "botnet" of linked machines, will phone home for new instructions.

What it'll do next is anyone's guess. It could muster enough silicon firepower to take down any Web site on the planet, or send out enough spam to fill the inboxes of every e-mail user on Earth.

Who Is at Risk?
Only PC users — not Mac users.
The virus attacks a vulnerability in PCs that are connected to a Microsoft server. Microsoft released a patch in October to prevent this, but if you never upgraded your computer and don't have the patch then you are at risk.
Bottom line: It's mostly for businesses because it's designed to target networks, not individuals. That doesn't mean you are not at risk though.

Why This Worm Is Tricky
It tricks your computer into thinking it already has the patch. That's why it's so hard to know if you have the worm or not.

How Do You Know If You Have the Worm?
Click here to get a free PC safety scan

If You Don't Have the Worm
Download the free Microsoft patch
Go to microsoft.com
Decide which operating system you use
Download, install and run the security patch
Note: This is to protect you before you get the worm. This was made available in October so many people who are diligent about keeping up with their upgrades already have this installed.

How to Remove the Worm
Go to microsoft.com
Download Malicious Software Removal Tool

Tips to Avoid Getting the Worm
Don't open attachments that you don't recognize
Don't open file that have .EXE or .COM at end of it
Don't plug personal laptop into your office computer
Keep computer upgraded; stop ignoring software updates