Microsoft Exchange Server 2013 Operating System (OS) Requirements

A friend of mine requested this; as you might already know that Exchange Server 2013 can be installed on Winwk12R2 and also optimized. But none the less older versions of windows server do support Exchange 2013…and the list follows

Exchange Server Version Compatibility

Version Windows 2000 Server Windows Server 2003 Windows Server 2003 R2 Windows Server 2008 Windows Server 2008 R2 Windows Server 2012
Exchange 2000 Server Yes No No No

No

No
Exchange Server 2003 Yes Yes Yes No No No
Exchange Server 2007 No Yes* Yes* Yes* Yes* No
Exchange Server 2010 No No No Yes* Yes* Yes*
Exchange Server 2013 No No No No Yes* Yes*
* 64-bit editions only supported