forse questo ti può aiutare (se capisci l'inglese):

1) Click Help on any Hotmail page (usually top right-hand corner).
2) Type Close Account in the keyword search section of the Help screen.
3) Click the Close Your Account link within the Help screen.
4) Click the go to the Close Account link that is highlighted in blue.
5) Read the instructions. When you are satisfied that you understand the terms associated with an account closure, click Close Account.

One note: if you're closing your account because you feel someone's abusing it, be aware that some time after you close your account, someone else could open a new one... using your old account name and pretend to be you.

I recommend just stop using it because that is the simplest thing to do.Personally, I recommend just stop using it because that is the simplest thing to do. However, in the interest of keeping your reputation safe, I'd also recommend that you do check in on it every so often to keep it active just to make sure no one else takes it. I believe the same approach is best for most all of the free email services.

In pratica se è tutto vero dice che si può chiudere un account, ma dopo un certo tempo qualcun altro potrebbe attivarne uno con lo stesso nome utente... quindi magari ti conviene lasciarlo inutilizzato, senza cancellarlo, per evitare abusi.