Thunderbird IMAP responded: User is authenticated but not connected

Anonymous
2022-12-27T12:29:12+00:00

Since yesterday, my Thunderbird client cannot connect to the outlook.office365.com IMAP server and other users at my university are also having this problem. I have deleted the stored token and redone the connection procedure but it does not work. I get two error messages:

The current operation on 'inbox' did not succeed. The mail server for account ... (IMAP) responded: User is authenticated but not connected.

Server outlook.office365.com has disconnected. The server may have gone down or there may be a network problem.

This does not work on any platform: Windows, Linux or Macos. Via the browser, we can access the emails but it is a workaround because it does not support openPGP. We need Thunderbird

Outlook | Web | Outlook.com | Account management, security, and privacy

Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

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Anonymous
2022-12-28T22:03:29+00:00

Hi Glenn,

Which version of Thunderbird are you using.

I have 102.6.1 which is the latest one. Can you try updating it if its not and then check.

Also under Thunderbird --> Click on the gear icon on the bottom left bar --> General --> Config Editor --> Show All

Type network.dns.dis in the search field

Select the very first option and click on the toggle arrow on the right, make it true

Close and reopen Thunderbird.. See if this helps

Let me know how it goes

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Anonymous
2022-12-28T21:34:14+00:00

Yes, it is worked for me too!

I just disabled ipv6 netwotking in thunderbird advanced configuration editor (network.dns.disableIPv6 = true)

and it is works again like a charm!

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  1. Anonymous
    2023-10-13T13:19:06+00:00

    The issue and workaround is very specific to the time when Microsoft broke just the IPv6 version of their service while keeping the IPv4 version running. You are experiencing a different issue not related to this thread.

    Please see https://stackoverflow.com/a/55190289 for different possible explanations for this error message or open a support ticket with Microsoft so they can provide you more details about what exactly is going wrong in your situation.

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  2. Anonymous
    2023-10-13T13:01:58+00:00

    Hi Glenn,

    Which version of Thunderbird are you using.

    I have 102.6.1 which is the latest one. Can you try updating it if its not and then check.

    Also under Thunderbird --> Click on the gear icon on the bottom left bar --> General --> Config Editor --> Show All

    Image

    Type network.dns.dis in the search field

    Select the very first option and click on the toggle arrow on the right, make it true

    Close and reopen Thunderbird.. See if this helps

    Image

    Let me know how it goes

    This did not work for me.

    VERY strange... I continue to get the Authenticated but not Authorized message - BUT ... I can SEND via SMPT.

    Just can't receive my emails.

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  3. Anonymous
    2023-06-27T18:17:31+00:00

    You can use Owl Exchange 1.2 add-on in Thunderbird .

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    1 person found this answer helpful.
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