3.1.4.1.5 wsa:MessageID
The WS-Management specification endorses two different MessageID URI formats, as specified in [DMTF-DSP0226] section 5.4.4.
Web Services Management Protocol Extensions for Windows Vista servers SHOULD<47> use the uuid:xxxxxxxx-xxxx--xxxx--xxxx--xxxxxxxxxxxx MessageID format. The MessageID value MUST be at least one character in length.
If the MessageID value is empty or missing the Web Services Management Protocol Extensions for Windows Vista server SHOULD return a wsa:InvalidMessageInformationHeader fault.