KB975426 - Virtual machines cannot migrate from a Windows Server 2008 stand-alone server to a Windows Server 2008 cluster after you upgrade to System Center Virtual Machine Manager 2008 R2
This new KB discusses an issue where SAN migration may fail with error 1600 after upgrading to to System Center Virtual Machine Manager 2008 R2.
VMM is unable to process one or more of the provided cmdlet parameters.
Type Get-Help NO_PARAM -full to view a list of defined parameters and complete descriptions. Then try the operation again.