My partner opened a new account. As far as I remember I've never set a password on this device. He hasn't either. I'm a bit reluctant to log out in case I can't get in again.
This'll teach me to not write things down in my own made up code :-)
I tried changing my outlook password last year and ended up locking myself out. I ended up having to create a new email account to reset my existing one and get a verification code. I think most accounts now have a 2 step verification process where you add your mobile number for additional security.