It sounds as if (probably) a cookie is saving the details, so delete all references to Outlook as shown under the heading 'How do I remove a single website from my history?' in this article - [[Delete browsing, search and download history on Firefox]], then try the site again. Even if that works, it's possible that you may have to choose one a/c or the other - unless you want to repeat the above process every time. ''If your question is resolved by this or another answer, please take a minute to let us know. Thank you!''