Unable to setup O365 Account


I am trying to setup my work O365 email, but I am receiving errors for both IMAP and POP3.


New Users can only post 1 media/ post, but the error reads: "Setup could not finish - Username or password incorrect. (POP3 SASL auth PLAIN authentication failed: -ERR Authentication failure: unknown user name or bad password.)

It is saying username or password is incorrect, but I verified multiple times that the username and password is correct by signing in successfully through office. com and even resetting the password and using the new one.

Settings I’m using:

IMAP - Using outlook.office365.com for the server, port 993, SSL/TLS

POP3 - Using outlook.office365.com for the server, port 995, SSL/TLS

Any guidance is appreciated!

I believe you need to use either an app password or oauth 2 for authentication with office365 when connecting from a 3rd-party email client.

Using your search engine of choice you should be able to find details on how to set up an app password for this. K-9 also supports oauth 2 for the outlook world, so that should be an option too.

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It worked with those instructions! Thank you both very much!