Hi Saxy,
I suggest you take a look at the official help center and forums for Windows Live, more specifically the subforums about the
Windows Live ID. In there, you'll see that more people would have reported the same issues. You can read those threads to see if they provide a solution and/or instructions.
Bottom line is that
you need to make a new post there, explaining your situation (account is blocked) and also include your Windows Live ID (that blocked email address) in question.
Note: email addresses in posts will automatically be hidden for the public.
People from Microsoft will then help you by checking your account and unblocking it.
However....
A possible reason why your account is sending out messages can be because you have spyware on your computer!
I highly adivse you to read
Account hijacks, what to do? and check the instructions and advise given there.
After that I also strongly encourage you to read
Important information about security.
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