Xen create VM Windows (Problem)

xe vm-start vm=MFSBSD
The server failed to handle your request, due to an internal error. The given message may give details useful for debugging the problem.
message: Xenctrl.Error [ memory 1696760 KiB free; to be scrubbed 0 KiB; total 7893 MiB]: 1: Operation not permitted


Only Windows VM...

Debian works !

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using ubuntu server 13.10