Try these: - incoming: outlook.office365.com, port 993, SSL/TLS, Oauth2 (assuming IMAP) - outgoing: smtp.office365.com, port 587, STARTTLS, Oauth2

I was using POP3. I deleted it and attempted to setup IMAP.

When I try to setup IMAP, I get the message: "Incoming server already exists.'

I have not found a way to get around this problem as there appears to be no option to delete the Incoming server.

That can be tricky. Sometimes exiting and restarting Thunderbird works. I suggest setting up account with just name and email address, nothing more

When I enter my name and email address with or without password I get the following message: Configuration could not be verified - is the username or password wrong?

The username and password are correct.

Can I edit data in the Thunderbird directory to add the data?

I do not think that this is related to EDGE, since I do not have EDGE on my WIN/XP, but most times that I use EDGE on WIN/10 then Firefox will not load until I do a reinstall of Firefox.

Please post screenshot of error message. did you finish setup or error during setup?

Error occurred when I clicked the Done button after entering name, email address, and password.

um, what version of Thunderbird are you using. That looks to be something from about 10 years ago and it is not going to work with oAuth and Outlook. Only recent versions contain the necessary code to use oauth on Microsoft sites. Hence https://support.mozilla.org/en-US/kb/microsoft-oauth-authentication-and-thunderbird-202

Perhaps try installing the current release version. https://www.thunderbird.net/en-US/thunderbird/all/

I updated to the latest version and it works. I will continue using POP.

I do not understand why when I updated Thunderbird to hopefully fix my problem, I did not get any indication that the version I was updating was an old version.