I’m infected with a net-worm, w32.wallz.
It was found on February 7 but not detected by AVAST (4.6-603) yet.
Checkout http://securityresponse.symantec.com/avcenter/venc/data/w32.wallz.html
Avast dev. team must be aware of it - is there a way to report them?
Please use the search option before asking.
Many questions have already been asked and answered on this board. (including yours)
http://forum.avast.com/index.php?topic=11132.msg94537#msg94537