Thunderbird Community Forum

I've downloaded the program to a second computer and put in my creditials and it's giving me an error "unable to log in at server. Probably wrong configuration, username or password." I've entered the correct info. Help

I have had an ongoing problem with Thunderbird being unable to log into the various mail servers that I use. I've tried repeatedly to solve this problem and have been able to cure it in the past by clearing the cache, but it recurs over and over again. I cannot keep wasting my time like this. I'm an independent contractor and I need to be able to use my e-mail client consistently. I've got work to do! This morning, it's suddenly decided that it cannot log into any of the three services that I use.

Is there a lasting solution to this problem? If not, please tell me and I'll move on peacefully, but please don't keep me chasing my tail for something that cannot be fixed.

I converted to Thunderbird 128,11.1esr in May 2025. My address book did not migrate to the newer version and I don't have the old one. Also, I don't know how to return to the previous version of Thunderbird.

can not send emails recently as about a month ago. Error message is :unable to authenicate to outgoing server. Please check the password and verifiy the authenticate method in account settings outgoing server . smtp not sure if i am doing this right? please help this old guy

I installed the update to Thunderbird as suggested this morning and my whole address book has disappeared. This is a major problem for me. Can you please tell me where it is and how to restore it to my account? Many thanks.

My messages displayed in Thunderbird are simply duplicated... I see a letter, and under it a reply with exactly the same letter. The date, time, and other data match. That is, two identical letters that were simply duplicated.

I'm in the process of cleaning up Thunderbird e-mail before moving to a new computer. I started with 11,593 e-mails in my Inbox and 7,799 e-mails in my Sent folder. I'm now down to 7,634 in my Inbox and 4,965 in my Sent folder. I've allocated 2 weeks for this process and found that it's taking me about 3 hours per day to meet my daily goals. I'm finding that I'm spending at LEAST half the time responding to "Empty-Trash/Compact-folders" requests. There are times I can delete 50 e-mails at a time without getting a request. Other times I will try to delete ten e-mails and get the request. With the old version of Thunderbird I could literally delete hundreds of e-mails at a time. Can you help? Russ Bukwa Yardley, PA ps. I have intentionally given you specific numbers. Based on my software- and test-engineering experience, I speculate you need to create a stress test to solve this nagging problem.

I have run Thunderbird for many years, no problem. Updated to version 139.0.2 today. Can no longer compose new email, clicking on +New Message elicits no response at all. Using the 'Send To Mail' no longer works. But I an reply to incoming emails. Turned off ad-ons & troubleshooting mode, turned off antivirus, made sure Thunderbird is a allowed program in antivirus (Avira). Nothing. Checked IMAP & SMTP, nothing changes, as far as I an see. Previous version was 115.

I find TB (sometimes, rarely perhaps) unable to recognise a mail's arrival although it has arrived. I chanced to discover this because I was expecting one and I kept trying get/fetch mails but kept on receiving the no new message status, but when I logged into the outlook mail server, I saw it there unread. Is there a way to trigger TB or outlook to resend or refresh, so TB can recognise and download it? Ofcourse I can do other things such as forward, reply with cc: etc., on the server but want to preserve the original in the TB folder.

appreciate any help?

thanks Raman

For a few days a banner persists on the lower left of the message window. It obscures content. ""Upgrade to Thunderbird Release"" I have checked twice to make sure there is no update available. Why does this annoying message persist after I run the update. I have rebooted the application multiple times. I do not want to click "Learn more" on the annoying banner promoting "Get monthly updates. with new features and improvements in the new Thunderbird Release" Is it malware? If the application is up to date why are you forcing me to "Learn more"? This is not a good user experience. My MacBook Air is up to date. Thunderbird release 128.11.1esr

I updated to 28.11.1esr (64-bit) and it's failed to get my Address book files- SERIOUSLY? They call this an upgrade? If they want me to donate (again) to Mozilla then this needs to be fixed. In the meantime how do I get all my addresses books back? Tried following the Google instructions but that led nowhere.

Hello,

Recently I have started to have emails fail to deliver to a certain domain and the message that comes back is

550 DKIM Sender Invalid - envelope rejected.

I am using Thunderbird v128.8.1 esr (64-bit). Extensions installed are: 1. Attachment Saver (Deimios, v.0.2.2) 2. FileLink provider for Send (Teal Dulcet v2.1.1) 3. Remove Duplicate Messages (Eyal Rozenberg v0.6.1)

I have been in communication with this client for several years and not had this problem before. When I send email to the same recipients using WebMail there is no problem, it is only when I send from Thunderbird.

I am not using any encryption type of setup.

Has anyone come across this before? Does anyone know of a solution?

Thanks, Franc.

Recently reminders from my google calendar keep on popping up. Suspect they popup when thunderbird checks for new mail. Snooze and dismiss give rise to an eror message

I have set up a Microsoft 365 account in Thunderbird to send and receive emails. Suddenly, I cannot receive new emails on Thunderbird. Even if I manually attempt to send/receive emails, new emails are not received. No error messages are displayed. When I log into Webmail (Outlook), I can see the newly arrived emails. Upon checking with Microsoft, they indicated that the root cause seems to be related to the failure in properly updating the UIDL map and UIDL history. Reinstalling the Thunderbird application did not resolve the issue. Could you please advise on how to address this problem?

When I receive some special html formatted email e.g. from ticket system like Zendesk they look like this: https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-17-01-06-32-c4ca42.png

When I want to reply to the text stays at the blue colored background and the text would be hard to read and it looks ugly: https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-17-01-06-37-c81e72.png

Unfortunately I can't change background color to blank or white in Tunderbird 139.0.2. In menu of reply window "Page colors and Background", "Use custom colors", "Background" I can set to #ffffff of course, click apply and ok, but that doesn't change it: https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-17-01-06-42-eccbc8.png

I suppose it relies to the html formatting of the received email because on starting to write a complete new email it works. But that's very annoying that Thunderbird doesn't manage to change background colors on already formatted html body. Is this a bug or only poor source code and the programmer didn't have much motivation to write and robust code which could gather all html emails?

Could you check with this test email to test and reproduce? https://limewire.com/d/pqbEk#1idjNje6b2

Thanks a lot! I'd be very happy about your help.

We’re having a weird issue with Thunderbird that’s showing up on multiple computers using the same mailbox. When we search using the top search bar (Ctrl+K), it often doesn't find all emails that clearly match the search term For example, we have multiple sent emails with the searched phrase in the subject, but Ctrl+K only finds one of them, even though there are two (or more) that match. When we use Ctrl+Shift+F (advanced search) with the exact same keyword and folder, all the matching emails show up just fine.

So it's not like the emails are missing —they're just not being picked up by the Ctrl+K search.

The annoying part is that Ctrl+K lets us open the whole conversation thread, which is really useful, while Ctrl+Shift+F only shows single messages.

Ive tried to:

- repair folders

- delete .msf files

- rebuild global database

- reenable "Include messages in this folder in Global Search results" but it did not help

And this isn’t just one machine, it's happening on every PC where this mailbox is used