zeszut--Perhaps MS Security Essentials. It is Beta and I do not believe you can get it at present from MS. They limited the number of users.
http://www.microsoft.com/security_essentials/
Supposedly you can get it here
http://www.softpedia.com/get/Antivir...sentials.shtml
http://www.winsupersite.com/win7/mse_beta.asp