Taking More Than One Snapshot of a Suspended Virtual Machine Produces an Error (1424776)
Why do I get an error message when I take a snapshot of a suspended virtual machine?
If you suspend a virtual machine and then take two successive snapshots, the second snapshot operation fails with the error Failure due to a malformed request to the server.
This error is expected and does not indicate a problem. Because suspended virtual machines do not change, the second snapshot would overwrite the existing snapshot with identical data.