SCVMM 2008 R2 KB 974869

KB974869 discusses some issues that might occur if the SCVMM 2008 agents from the original version of Virtual Machine Manager 2008 remain after you upgrade to SCVMM 2008 R2.

Solution:
Manually upgrade all remaining agents to Virtual Machine Manager 2008 R2.

Warning (2927)A Hardware Management error has occurred trying to contact server . (Unknown error (0x80338041))

Error 0x80338041: The SOAP XML in the message does not match the corresponding XML schema definition. Change the XML and retry.

Error (2927)A Hardware Management error has occurred trying to contact server . (Unknown error (0x80338001))

Error 0x80338001: The WS-Management service cannot process the request. The WS-Addressing action URI is invalid. Check the documentation for information on how to construct an action URI.

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KB974869 - You receive a warning 2927 and an unknown error when you create a virtual machine from a VHD file after you upgrade to System Center Virtual Machine Manager 2008 R2