I had just opened a new Hotmail account & mail, and was still "signed in" to IT.   I then tried to access my Bell Mail account & mail and couldn't figure out why I couldn't get into it.  It prompted me to reset password and so I did.  It was only shortly after that I realized (the problem all along was) ...that you can only be signed in to one account at a time.   Learning curve!  When I then tried to again reset my password for the Bell account to my original and PREFERRED password it wouldn't allow it.

Can you NEVER return to a former password... or is there a time frame involved... or is there a contact # for support to override this blockout?