November 2014 Update Rollup for Windows Server 2012 and 2012 R2 was released a couple of days ago but many users had found a critical problem with VSS Writer that stops all the backups. Hyper-V, Exchange Server and SQL Server no longer working with this update. There isn’t a documentation about the bug but in meanwhile to resolve the problem is necessary uninstall, or not install, the KB3000853.
IMHO this is not a good advertising for Microsoft because is the first “big patch bug” for Windows Server 2012 and 2012 R2 in a moment where Microsoft tried to push the philosophy “keep updated your servers”.
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