Hi Neeleshk pranaams.
OK, there all good programs, the first has a fix n works well with L/W, Dont forget to update before running scan.
sounds like a virus....
Check your system using any of these programs (I reckon using all of them):
http://www.grisoft.com (good free AVG)
http://www.ewido.com (>>now called AVG Anti Spyware<< free 30 day trial -the best in my opinion)
http://www.ccleaner.com/download/ (free)
Spybot - Search & Destroy (FREE)
You can also read here point 4 in the post of LOTR....:
http://www.gnutellaforums.com/showthread.php?t=41432