from a  few days i have been receiving an error masg that  "task manager has been disabled by your administrator" on my XP. I have  only one user on my pc and that is the  administrator which i use , then how can the task manager be disabled.....HELPThis may help....

http://www.pchell.com/support/taskmanagerdisabled.shtml
Method # 5 will work but there must be a bug or virus on your computer. You should check out Computer virus and Spyware on this forum and have your computer checked out. OR, if you have Windows XP Professional, try this:

- Click Start
- Click Run
- Enter gpedit.msc in the Open box and click OK
In the Group Policy settings window
- Select User Configuration
- Select ADMINISTRATIVE Templates
- Select System
- Select Ctrl+Alt+Delete OPTIONS
- Double-click the Remove Task Manager option

I don't think it's MALWARE.I didn't think it was malware either or I would have pointed him the spyware forum

OP is i have gone through Carbon Dudeoxide but when i enter administrative templates it shows timer then i cant see system.I too  GUESS something is wrong.when i sign in to yahoo messenger then when i keep it minimize, it comes on screen  and then automatically status is changed.Download HijackThis:
http://www.trendsecure.com/portal/en-US/tools/security_tools/hijackthis/download
Click on Download HijackThis Installer
Post HijackTHis log.