As part of regular update of our antimalware technology to address the latest in the threat landscape, MMPC is planning to release a new antimalware engine on 17 Jan 2011.
Affected products: Microsoft Security Essentials, Forefront Client Security, Forefront Endpoint Protection, Windows Intune Endpoint Protection.
Engine Version will be in the range of 1.1.800X.0
http://blogs.technet.com/b/enginenotifications/archive/2012/01/15/new-antimalware-engine-is-planned-for-release-on-17-jan-2011.aspx