I would call this "Abuse" and so you should report this to Windows Live directly.
This Microsoft Answers forum replies show you how to do it;
http://answers.microsoft.com/en-us/windowslive/forum/hotmail-email/how-do-i-report-abuse-or-spam-in-hotmail/703b31d1-0381-4240-90ef-ff3c4ba66fad
Good luck.
Mark
Whilst probably not the best question title, I can't find out how to report a person (or bot) that is constantly trying to access my account.
In the last hour, I've had 23 emails from Live with the following message, which is sent out when someone uses the 'forgot password' system:
'Please use the code xxxxxxx to use your Windows Live ID from an unrecognized computer.'
How do I report this?

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