Windows 2012 / Exchange 2013
188.8.131.52 and later
A dynamic link library DLL (MSExchangePS64.dll) initialization routine failed (MS Exchange 2013 Server Backup)
This issue can occurs if the .NET Framework 3.5 Features is not installed on the affected Windows 2012 Server.For server backup of Exchange 2013, the .NET Framework 3.5 Windows features must be installed.
To resolve the issue, please install the .NET Framework 3.5 Features on the corresponding Windows 2012 Server: