I'm sorry to read about the theft and hope that you are successful in getting the PC returned to you and the thief apprehended.
The last information that I was provided was that the local law enforcement agency with an active case can contact Microsoft and request this information officially. Law enforcement has a special number to call (I do not know this number) and they will need to take care of the legal paperwork to make the request. They will need to know your subscription information, PC name, and other information related to the account and that PC. That still does not guarantee that they can provide anything useful to help locate the PC, unfortunately.
The most recent request for this has not yielded any satisfactory results.
-steve
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