Although i'm not a win user i should save a pc in my home running video software and running the hated window$ ...
This software after a long research was the "MALWAREBYTES" (link: http://www.malwarebytes.org/ )
Don't forget the very good anti-virus AVIRA that also found many viruses and malware in this pc and the Symantec endpoint protection didn't find ANYTHING !!! (link: http://www.free-av.com/ )
Finally a very interesting and helpfully program is "Process Explorer" from Mark Russinovich (link : http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx )
A very powerful and with continuous updates tool as anti-spyware is the "SUPER-ANTI Spyware" (link: http://www.superantispyware.com/ )