This thread might give you some idea ... Seems like you need to install and run effective anti virus sofrware and anti spyware, and give your comuter a thorough clean out, in respect to spy ware and viruses, without delay
http://www.gnutellaforums.com/showthread.php?s=&threadid=40979&highlight=virus+and+size
That thread is one of the links from
http://www.gnutellaforums.com/showthread.php?threadid=41432
