We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

How do I get Thunderbird to connect to a properly-configured Office 365 mail account after shutting down and then restarting the client?

  • 3 replies
  • 65 have this problem
  • 39 views
  • Last reply by milchsage

more options

I get my Office 365 account set up and working in Thunderbird. I can download and send mail just fine using the auto-detect or manual account settings recommended by Microsoft/Outlook/Office 365. Everything appears to be working as it should as long as the client stays open. When I shut the Thunderbird client down and restart it, it can no longer access the Office 365 mail account. I get a popup error message:

The current operation on 'Inbox' did not succeed. The mail server for account (my Office 365 account) responded: User is authenticated but not connected.

It has no problem connecting to Hotmail, Gmail and other email services, and I can access Office 365 through the web client, but Thunderbird refuses to connect. If I remove the account and re-add it, I can have full access to my email again, but only as long as Thunderbird stays open. If the client gets restarted, it's gone again.

How do I fix this?

I get my Office 365 account set up and working in Thunderbird. I can download and send mail just fine using the auto-detect or manual account settings recommended by Microsoft/Outlook/Office 365. Everything appears to be working as it should as long as the client stays open. When I shut the Thunderbird client down and restart it, it can no longer access the Office 365 mail account. I get a popup error message: The current operation on 'Inbox' did not succeed. The mail server for account (my Office 365 account) responded: User is authenticated but not connected. It has no problem connecting to Hotmail, Gmail and other email services, and I can access Office 365 through the web client, but Thunderbird refuses to connect. If I remove the account and re-add it, I can have full access to my email again, but only as long as Thunderbird stays open. If the client gets restarted, it's gone again. How do I fix this?

All Replies (3)

more options

I'm having the same problem, on (at least) two different computers. It's clearly a new problem--this account worked fine with Thunderbird until a day or two ago. And it's clearly a Thunderbird problem--I can still access the account just fine through Outlook. So what on earth is happening, and how do we fix it?

more options

I think you might be having a cached password problem. I was having it and was able to resolve by deleting my stored password in Thunderbird. I referenced http://kb.mozillazine.org/Setting_and_changing_email_passwords and also posted my question and resolution: https://support.mozilla.org/en-US/questions/1015221#answer-615054

more options

It's solved here: http://community.spiceworks.com/topic/372289-heldesk-not-sending-emails-through-office-365

You need to open both ports (587 and 993) for inbound AND outbound on your firewall.