First, stop the bug from running by hitting CTRL-ALT-DELETE and
bringing up the task manager. Look for msblast.exe in the list, and
kill it. Now your computer won't shut down, but the bug is still there
and will run the next time you start your machine. Go to this URL to
find out how to get rid of it:
<http://securityresponse.symantec.com/avcenter/venc/data/w32.blaster.worm.re
moval.tool.html>