Hello,vamsikrishna & Welcome

Hmm ok did you go right to Windows update site & download
all updates for the OS, or where you going online when this happen
are you running a Virus scanner if so is it up to date.

did you run a full system scan with the Virus scanner
if you have one at what point did this all start

now do this here if you can

Go for free online Virus scans here:

http://housecall.trendmicro.com/hou.../start_corp.asp
http://www.pandasoftware.com/activescan/

Be sure and put a check in the box by "Auto Clean" before you do the scan. If it finds anything that it cannot clean have it delete it or make a note of the file location so you can delete it yourself.

then let us know if anything was found

HGD