The computer-speak term for this situation is "account compromise," use this term when communicating with the Live support folks.
Your Hotmail account is now owned by the folks at Windows Live, which is why you will find the Windows Live help topic for this under
Account Compromise - Unauthorized Account Access.
Go now to http://account.live.com and add Password Reset Information to your account and encourage your
friends and family to do the same.
If you are the hacked/hijacked account owner:
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