Graham Ramsay bashed at the keyboard and said :

Just a warning.
Looks like there is a mass hack on at present to
exploit the latest security hole. If your PC keeps
wanting to re-boot with the rpc service failing
then you need to get the fix from windows
update and activate your firewall.
The fix you need is:

Buffer Overrun In RPC Interface Could Allow Code Execution (823980)

Just something else to follow that up with:
http://www.symantec.com/avcenter/ven...ster.worm.html