System Authority Problem in XP

Why don't you just call toll free number of Microsoft

prateek thats an extremely useless answer.

justhink, looks like your infected with the sasser worm. Here is a free link to remove the sasser worm:

*www.able2know.com/go/?a2kjump=*www.microsoft.com/security/incident/sasser.asp

Also I would sggest you have a good Antivbirus Solution such as Avast! which is free for the home edition.

Avast can be found here.

*files.avast.com/iavs4pro/setupeng.exe

Also make sure you keep your computer updated with the latest security patches and updates. You should apply these patches immediately once you use the removal tool to prevent future incidents.
Windows XP - KB835732
Windows 2000 - KB835732

i thought this was the BLASTER worm's symtoms?
*securityresponse.symantec.com/avcenter/venc/data/w32.blaster.worm.html

Both of them share similar symptoms. Nothing good old Windows Update cant protect.

lovesan or sasser infection.

it had happened to me too earlier ! you've been infected with sasser or the lovesan virus. first run your virus scan (avast) at boot time or safe mode using deep-scan modes. then download and use the latest sasser removal tool. then patch up your pc with KB835732 patch. it solved my problem. hope it solves yours too.