How to remove your Microsoft account
Warning: use the direct link for closing your entire Microsoft account (formerly known as Windows Live) including Live Mail and other services!
Direct removal link: https://account.live.com/CloseAccount.aspx
Helpful Trick: Removing online data
Publicly visible text/images often aren’t properly removed even when you succeed in removing an account. Try editing or removing them manually before removing the account itself. If you’re unsure what happens to your tracks: this can be found mostly in the Terms of Service/Privacy Policy; otherwise you can always contact Microsoft and ask personally. By the way, removal requests don’t necessarily mean your data will actually be removed (e.g. due to legal obligations).