Όλα τα συμπτώματα που αναφέρεις οδηγούν στον W32.Blaster.Worm.
Ενδεικτικα απο το site της symantec:
Because of the way the worm works, it may be difficult to connect to the Internet to obtain the patch, definitions, or removal tool before the worm shuts down the computer. It has been reported that, for users of Windows XP, activating the Windows XP firewall may allow you to download and install the patch, obtain virus definitions, and run the removal tool. This may also work with other firewalls, although this has not been confirmed.
Πιστεύω να σε βοήθησα. :) :)