NT Authority system keeps shutting down my computer. How can I get rid of it?
Sounds like you have the Blaster worm. Microsoft provides some background information and removal instructions: http://support.microsoft.com/?kbid=826955.
You also need, need, need to configure a host firewall and antivirus software.
Dig Deeper on Windows Operating System Management
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.