Finding associated email account in hotmail

Hello,

When signing up with hotmail, you are asked for an existing email address.

Is there a way to find that existing account name provided that you have any associated account?

If you dont understand. I make an account (X), and use account (Y) as my existing account. Is there a way to find (Y) if i have (X)?

Anyway, i need to find a person. I dont think they are using the (X) account any more, i dont know their last name, nothing but their email, age, gender, approximate location, interests etc. This is a lost friend.

This is the only idea that has a chance of working, because i have tried everything else, like, social networking sites etc.

Any info is appreciated or suggestions on how to find this person.

Please help, thank you.