Error:
Setup can't continue with the upgrade because the MonAgentCore (3420) has open files. Close the process, and then restart Setup.
For more information, visit: http://technet.microsoft.com/library(EXCHG.150)/ms.exch.setupreadiness.ProcessNeedsToBeClosedOnUpgrade.aspx
Exchange 2016 was successfully installed, this is a VM on Azure. I had no issues installing at first but upgrading the CU2 or CU1 is a nightmare.
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