Actually first was www.hotmail.com
and when they changed their domain from hotmail to live all existing IDs were asked to convert their account or choose new alias for www.mail.live.com
instead of www.hotmail.com.
Same as when they changed again from mail.live.com to outlook.com all existing users were again asked to convert their account from mail.live.com to outlook.com or choose new alias on outlook.com instead of www.mail.live.com
Myself is the witness because I created at hotmail than changed to live.com and now changed to outlook.com There was a period set for every change and after that all accounts would be assumed blocked/disabled or may be removed.
I think you have the same case that you not converted your account