Clamwin AV

ClamWin Antivirus is an open source antivirus scanner for your Windows device. It comes with a GmL licence and has been adopted by over 6MM,MMM users worldwide. Apart from a regularly updated virus definitions database, Clam AV also offers scheduled scans and comes with an add-on for MS Outlook. Sadly, Clam AV does not offer realtime antivirus protection.

Website: http://www.clamwin.com/