Haunted by a virus I think!!
See point 4 here
http://www.gnutellaforums.com/showth...threadid=41432
What have you been downloading lately? Make sure you have a good, updated AV program. Scan a file before you open it. There's good info & advice in that thread. Also a link to norbiesworld. If you can't get rid of the virus, he'll be able to help you