Thunderbird Community Forum

Thanks in advance. I'm trying to get Thunderbird setup with an outlook.com email address. All the default server settings look fine. I know the email address is good since I can login via a web browser. Cookies enabled and all the other recommended settings including app password. Yet it keeps saying Unable to log into the server. Has anyone successfully done this with the latest version of Thunderbird. I'm on Zorin 18 Pro.

Regards,

Mark Verhyden

The system was working fine. The next day, when starting Thunderbird (TB, the status line shows logging in to server but loops; no errors or messages, Thunderbird is 'locked out' spinning. I see the normal INBOX page, but logging in never completes. NO CHANGES were made to TB accounts or settings. I have re-installed TB, re-booted, but no change. I cannot check/change any of the accounts or do any further 'debugging' because TB is spinning. The server login is fine because Webmail can be used. Internet connection is fine, because browser works. 1. How can I stop TB from trying to login at start up? 2. What could/would cause this behaviour?

Any suggestions much appreciated.

On upgrade to 152.0, a pop-up asked for options I have not seen before. I cannot find info about what the net.thunderbird option is, nor why I would or would not want to click it? Any help out there?

Thanks!

All of a sudden every time I open something in an email it automatically creates a new tab. When I delete what I have open it takes me out of my email account and I have to delete the tab to get back to my remaining emails. I have changed nothing so I am confused as to why it has recently changed.

Hello,

we have a reproducible issue in Thunderbird when forwarding emails with attachments.

Environment: Windows 11 Professional Thunderbird version 152.0 (The issue also occurred in the previous Thunderbird version) POP3 account Mail provider Strato AVG Business Antivirus installed, but the issue also occurs after testing AVG related settings Issue occurs with different attachment types and sizes, for example PDF and DXF files

Steps to reproduce:

1. Open an email with an attachment. 2. Forward the email using Forward Inline. 3. Add recipient and some text. 4. Save the message as draft. 5. The first save works. 6. Save the same draft again, with or without changing the text.

Actual result: The second save fails with an error message similar to:

“Your message cannot be saved as a draft. There was an error attaching [filename]. Please check if you have sufficient access rights to the file.”

Expected result: The draft should save repeatedly without an attachment error.

Important observations: The problem occurs with all tested attachments, not only one specific file. The file size does not seem to be the cause. The issue also occurred with a small DXF attachment of about 355 KB. The issue also occurs in Thunderbird Troubleshoot Mode. The issue still occurred after creating a new Thunderbird POP3 profile and downloading the remaining emails again from the Strato POP3 mailbox. Changing the draft folder did not solve the issue. Removing temporary Drafts files and rebuilding the Drafts index did not solve the issue. The issue originally appeared to be related to AVG, but later tests showed that AVG is not the main cause. If the automatically inherited attachment is removed from the forwarded message and then manually dragged again from the original email into the draft, the draft can be saved without problems. Changing forwarding mode from Forward Inline to Forward as Attachment solves the issue.

Conclusion: This looks like a Thunderbird issue with automatically inherited attachments in inline forwarded messages. The first draft save works, but on the second save Thunderbird seems unable to reprocess or resolve the inherited attachment and shows a misleading access rights error.

We would appreciate any advice on how to further troubleshoot or resolve this issue. If this is a known bug, we would also be grateful for any information regarding a planned fix or available workaround. We are happy to provide additional information, screenshots or perform further tests if needed.

I imported an appointment into the calendar. I wanted to setup a reminder. The only option is "Show an alert". Is it possible to to create a reminder option other than "Show and alert"?

Did I dream seeing an ad for a new system for sorting incoming emails to what I would call folders, but I think it had sections like Work, Home, Family etc.? Can't find anything on it. I would love to be able to park stuff in separate folders without me actually doing it!

I just upgraded from thunderbird 140 to 152 on Windows 11. I have master password setup.

Every times I start thunderbird, calendar keeps asking for authentication ( oauth ) , I did login successfully and was able to view and modify my events.

After a couple of startup I decided to click on the close button of the oauth authentication windows for calendar. I still able to see and modify my calendar successfully. Is it a bug or I miss something in the calendar settings  ?

Thanks

roland.multhaupt

18. Juni 2026, 07:13 GMT-6

Firebird is so slow now, that I can rarely receive the code that you send me. Have to take annother programm for that. Freezes even when trying to mark a mail or erasing it. WIN 11. The programm is working well at my wifes laptop also WIN 11. 2 month ago it worked fast and fine. Working in Troubleshooting mode does not show any spam ordner like before and it does not run better. I also downloaded the last version. No change! I would like to uninstall the programm but did not dare due to perhaps loose all my mails. Could you help me please? Thank you!

When I try to access my e-mails I am getting message." Login to server pop.tiscali.co.uk with username [redacted]@tiscali.co.uk failed." Nothing I do helps

Someone suggested BetterBird would be better for me than Thunderbird, but I'm not sure it was the right decision. They said I should be able to just open Thunderbird and it should work as they have the same base code, but it doesn't. Any ideas? I have 8 email accounts, so I'd hate to start from scratch.

Dzień dobry Mam taki problem, W programie Thunderbird mam skonfigurowane dwa konta obydwa na ....o2.pl Na jednym koncie co jakiś czas w folderze "Odebrane" znikają wszystkie wiadomości i po jakimś czasie pobierają się o nowa wszystkie nagłówki (co oczywiście trochę trwa) ale problem jest w tym że znikają mi zaznaczone etykiety. To bardzo utrudnia mi pracę z tym programem. Na tym drugim komcie nic takiego nie występuje. Sprawdzałem w konfiguracji serwera oba IMAP wszystko tak samo także w synchronizacji i pozostałe ustawienia takie same. Może ktoś pomoże ja w tych tematach jestem mocno w tyle :) Za pomoc z góry dziękuję Marek

Greetings all!

Thunderbird version is 1.52.0

Since this morning (8:00 CET) I have to enter password for my google calendar every time I start Thunderbird. No matter what authentication options I choose, calendar manager keeps asking me to authenticate. "Don't ask again" is turned on. Gmail is set up as OAuth for both incoming and outgoing servers, and it works fine.

Things I've tried since:

- Removed legacy connection in password manager, when I was using IMAP to connect to Gmail - Revoked OAuth permission from google account for Calendar and from Thunderbird password manager - Unsubscribed from calendars and added them again after restarting Thunderbird

I don't know what more to do. Also, I don't know what happened, really, as it worked properly last night.

I don't know what to do when February 29 is in my calendar, 2026 is not a leap year. I've found nothing to help me. I have the latest version if Thunderbird. Thanks

I am getting a lot of email dated a month of more in the future. How do I best filter these out as junk? I tried making a regular filter, but can't find a way to set it to "greater than today."

Within the last 6 weeks I migrated to Win11. I migrated my apps that would work and Thunderbird also. Got a recent update of TB. Finally MOSTLY disabled the bloody awful thread thing in TB (seems to be folder specific??!).

But ever since running on Win 11, I cannot stop TB from marking my messages as read even if I have never opened them. Even If I never use another device to connect with email. I try things and sometimes it works for like a day and then poof! : any email that comes in is read as per TB.

It is killing me. I run my biz on email and if it is unread I give it low priority. But turns out it is marked read without any action from me. I get a LOT of emails.

Really! I do no want to migrate to another email program.

I am fluent with regedit and can hack a .ini file. Point me in the right direction please.

help!

Good morning, for some time now, appointments on the calendar that were scheduled before I open Thunderbird have been “forgotten” and don't appear. For example: an appointment (or memo) at 8:00 a.m.; I open Thunderbird at 9:00 a.m., and the appointment doesn't show up. Thank you.