Backtrack:  
 
by lunarg on February 22nd 2013, at 13:03

Although unsupported, it is possible to install Microsoft Security Essentials on a Windows Server 2012.

To do this, set the compatibility of the downloaded file to Windows 7, then start that file with the parameter /disableoslimit.

The installation goes without a problem, and as far as I can tell, there are no compatibility issues.