KB2750149 breaks Failover Cluster MMC in Windows 2012

Microsoft released an update KB2750149 for .NET 4.5 which fixes some reliability, compatibility, stability, and performance issues. When this update, however, is installed on Windows 2012 Failover Cluster, the cluster management MMC stops working. The cluster works as expected; the issue is only with the management, however, the cluster can still be managed remotely from a server that does not have this KB installed.

I received this error on VMM server while trying to open up cluster mmc to manage Hyper-V cluster. MS is investigating the issue and the fix for now is to uninstall this update. As VMM needs .NET 4.5, this update needs to be removed until further notice :=)

A weak event was created and it lives on the wrong object, there is a very high chance this will fail, please review and make changes on your code to prevent this issue at MS.Internal.FailoverClusters.FrameWork.WeakEvent…. …

Note:

“Ask the Core Team” blog has a blog entry about this and states the blog post will be updated when the resolution is available: http://blogs.technet.com/b/askcore/archive/2013/01/14/error-in-failover-cluster-manager-after-install-of-kb2750149.aspx

UPDATE: 1/27/2013

A new patch is  now available to fix this issue. After you install the .NET patch (2750149), you need to apply KB2803748.

#FailoverCluster #Windows2012