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I get an error message saying the user was able to authenticate but could not connect.

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  • 1 has this problem
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  • Last reply by wpmc

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Hi, I'm trying to put my school email on thunderbird. I contacted my school and they said theres nothing wrong with the school email. I'm trying to connect to office 365. The microsoft 365 login works, and I enter my username and password. But once I logged in and try to load my inbox I get that error message. It says I was authenticated but couldn't connect.

Server Type: IMAP Mail Server Server Name: outlook.office365.com Port: 993 user name: olmay@cougarnet.uh.edu Connection security: SSL/TLS Authentication method: OAuth2

Hi, I'm trying to put my school email on thunderbird. I contacted my school and they said theres nothing wrong with the school email. I'm trying to connect to office 365. The microsoft 365 login works, and I enter my username and password. But once I logged in and try to load my inbox I get that error message. It says I was authenticated but couldn't connect. Server Type: IMAP Mail Server Server Name: outlook.office365.com Port: 993 user name: olmay@cougarnet.uh.edu Connection security: SSL/TLS Authentication method: OAuth2

All Replies (1)

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Hello Olivia.

Well, your issue seems odd to me in a way since I am not personally familiar with the office365.com e-mail service, but that is irrelevant here. You say that you are able to log in and it can authenticate your login credentials but you can not connect to the server to access your e-mail messages.

So, if you can't connect to your account through Thunderbird at the moment, are you able to log in via a web environment, like office365.com's website, and access your e-mail that way? I ask since it does appear as if you have access to a webmail environment, if wanted, no? If you can log in via the webmail environment and access your e-mail, at least that will be something to begin with. If you are unable to access your school e-mail messages through the webmail environment, that opens up some more questions, like what is wrong? Outgoing:

   Server hostname: smtp.office365.com
   Port: 587
   SSL: STARTTLS
   Authentication: Oauth2


As you are wanting to use the IMAP protocol for receiving e-mails, which SMTP server are you using? When looking at some sites online, it appears that the correlating SMTP server for office365.com would be as follows: Outgoing:

   Server hostname: smtp.office365.com
   Port: 587
   SSL: STARTTLS
   Authentication: Oauth2

As for the username, you would use your e-mail address at uh.edu in that spot.

Beyond that, I'm wondering if maybe the e-mail servers at office365.com could just be unavailable at the moment that you tried to connect to them? Who knows. Either way, good luck in getting this resolved.

Will

Modified by NoahSUMO