Hi Deependra,

sounds like your pc doesn't want to play fair... Have you updated anything recently either hardware or software before all this started happening? Just to be on the safe side lets run through the basics and run a anti-spyware and anti-virus program please. You could also boot into 'safe-mode' (press F8 when booting pc) and see if the utilities will update then. If they do then you'll know it's something driver based thats causing the problem.

__________________