Three old virtual servers were showing as VM Additions Not Detected in System Center Virtual Machine Manger 2012 SP1 (VMM).
Choosing to Install Virtual Guest services didn’t resolve the problem as they were already listed in Add Remove Programs and installed. Mouse integration was working without having to use CTRL-ALT-LEFT, but I was unable to use the Shut Down command from VMM.
Device Manager showed no errors, but the Event Log was showing errors for the failure of the following services to start: Hyper-V Heartbeat, Hyper-V Data Exchange, Hyper-V Guest Shutdown, Hyper-V Time Synchronization and Hyper-V Volume Shadow Copy Requestor.
A closer looked showed two Hyper-V integration components entries in Add Remove Programs: Hyper-V Integration Services (version 6.2.9200.16384) and Microsoft Hyper-V Guest Components.