Thunderbird: Free Your Inbox

PSA: We're aware of an issue affecting #Thunderbird users using #IMAP to connect to certain #Microsoft account servers (for example: outlook.office365.com).

These users are receiving an error message that says "User is authenticated but not connected."

We believe this is caused by Microsoft running certain services with broken #IPv6 functionality.

WORKAROUND: Disable IPv6 networking in Thunderbird's advanced config.

MORE INFO: https://answers.microsoft.com/en-us/outlook_com/forum/all/thunderbird-imap-responded-user-is-authenticated/062a82f6-e678-4462-88b7-dd6cc318386f?page=1

Redirecting

Jan 5, 2023 at 12:49pmWeb
Show threadMartinJan 5, 2023
@thunderbird I deleted Microsoft completely instead. Also works great 😅
Show threadThunderbird: Free Your InboxJan 5, 2023
@MartinH This is a 100% legitimate solution 💙
Show threadtimviseeJan 5, 2023
@thunderbird it's sad how painful IPv6 still is
Show threadPadraig 🌈Jan 5, 2023

@thunderbird it could also be that Basic Authentication (IMAP and POP) is being turned off for everyone this week!

Modern Authentication is required which doesn't work natively on TB

Show threadNathan Phillip Brink (binki)Jan 5, 2023
@padraig @thunderbird But… we have been forced to use OAuth2 for months already and it was working great, even over IPv6, prior to Microsoft breaking things on 2022-12-26 or 2022-12-27. I do not think this is related. It is some Microsoft internal thing whose details we will never hear about. My theory is that ratelimiting and CIDR techniques that work with IPv6 don’t work with IPv4 (since Microsoft has used this error message in the past when you are being ratelimited).
Show threadThomas Steen RasmussenJan 5, 2023
@thunderbird this was fixed this morning (CET), see the end of the thread you linked
Show thread9Lukas5 🚂 🐧Jan 5, 2023
@thunderbird That would kill the connection to my own server that's IPv6 only inside my home network 🫣
Good thing I don't have a MS Server I need to connect to badly 😅
Show thread❄️ freezr ❄️Jan 5, 2023
@thunderbird How unexpected... ​
Show thread👻 scary ipv6-only networks 👻Jan 5, 2023
@thunderbird does #thunderbird support #happyeyeballs (i.e. #rfc8305 / #rfc6555 ) behaviour w/r/t #ipv6 connectivity?
Show threadJarek Jan 5, 2023
@noipv6 #happyeyeballs work on the TCP connection level and would help to fallback to IPv4 if IPv6 connection wouldn't be possible to establish. Here as far as I understand the TCP connection is established, but fails on the application level. Happy eyeballs wouldn't help.
Show thread👻 scary ipv6-only networks 👻Jan 5, 2023

@Jarek as i joked (?) earlier this week, “time for happy eyeballs v3, which falls back in the event of 4xx/5xx http responses 🥴”

(& other connection issues like you describe 😔)

Show threadJohn W. O'BrienJan 5, 2023
@noipv6 @thunderbird Would Happy Eyeballs even make a difference in this case?
Show threadNathan Phillip Brink (binki)Jan 5, 2023
@thunderbird I think this was resolved by Microsoft 12 or so hours ago.
Show threadalarigJan 6, 2023
@thunderbird @ButterflyOfFire Also: stop using Microsoft email services and enable back IPv6
Show threadKristianJan 6, 2023
@thunderbird disabling IPv6 is never the workaround. disable mail instead.
Show threadTuxicomanJan 9, 2023

@thunderbird

Microsoft provide no support except "we receive your message". Do people pay for that?