Here is how you might solve the issue. This is the very last resort that worked for many others.
Open a brand new MSN/Hotmail account. Once connected, go to this page
Click on "additional resources" and then click on "ask a question on the Hotmail forums.
Explain the situation in detail. A Hotmail moderator should give you the solution within 24 to 48 hours.
Good luck and please let me know