Your antivirus can't stop the MS Blaster or other WORMS.

It's why SP1 and the Windows Update patches are so important. Without them or other measures, your machine will be infected without much ado.

Here's an article about ONE of the Worms. Remember you have to identify which worm since using the MS Blaster cure won't fix the Nachi worm and so on.

http://securityresponse.symantec.com/avcenter/venc/data/w32.blaster.worm.html

A scan with the Anti-Parasite Suite (all 5 scans please) usually finds which pest it is: http://reviews.cnet.com/5208-6132-0.html?forumID=32&threadID=1313&start=0

Bob