My Windows XP Service Pack 2 OS computer repeatedly runs into a NS Authority Shutdown, something about the RPC being terminated. I have gone through numerous threads and have found that this error is caused by MSBlast... or other worms that do similar to MSBlast, the problem is that I have done a full system scan with Norton 360 2008 and I have found no viruses, worms or Trojans. The error occurs on at almost random times, sometimes my computer could be on for an entire night and it doesn't happen and at others staying on for 30 minutes could already cause it. Although the error is the same as the error caused by MSBlast worm but the irregular intervals of the error occurring is different from MSBlast I've also been through the steps to remove MSBlast and Sasser but according to the removal steps, I don't even have them so... I'm on a bit of a blocked road right now I could easily system restore, but I have hell of a lot of stuff and I have misplaced my spare portable hard drives so I can't back them all up. Any help or suggestion would be greatly appreciated. Oh and another problem which shouldn't really be in this thread is that, my when I try accessing my emails in Windows Live Messenger (by pressing the Letter button under the name) instead of taking me to hotmail's website I go into Outlook Express how do I stop it from doing this?