Reg.exe – Pre Service Pack 2 Revision History for Windows 7 SP1, Windows Server 2008 R2 SP1 and Windows Small Business Server 2011 (SBS 2011)
08-Oct-2012 – 6.1.7601.22128 – Reg.exe – x86/x64 – http://support.microsoft.com/kb/973817 – The Reg.exe utility does not compress a registry key when the utility saves a registry key to a hive file on a computer that is running Windows Server 2008, Windows Vista, Windows 7 or Windows Server 2008 R2