Managing personal Outlook.com account settings, security, and privacy
I am having the same issue. The account I created was 17 or so years ago and I use it all the time - up until a few days ago, I could no longer pick up any emails. I have tried going through the recovery process/reset password process. However, I no longer have the mobile number I used when I set it up, cannot remember the password, and cannot remember any recently used email addresses let alone subject lines of those emails.
How do I get back into my account?