Thunderbird Community Forum

I have been using Thunderbird for my email for a number of years now. I don't understand why, when I repeatedly block a particular email, the 'blocked' email message comes through to my email box anyway.

I want email addresses I block TO BE BLOCKED from getting to me...Please...

I recently installed 128.10.2esr (64-bit) on a Win11 computer. There's no option under "View, Toolbars" for it. Was it removed in this version or am I missing something?

I recently updated Thunderbird to Nebula v139.0 and now my "Recent Destinations" list is not saving all my folders in its list after moving / copying emails to the destination folder I selected. It seems that the "Recent Destinations" list is only saving (or maybe just displaying) folders with names beginning with "A" - "N". If I move an email to a folder with its name beginning with "O" - "Z", the email will be moved to the appropriate / selected folder, but the folder (destination) name will NOT appear in the "Recent Destinations" list.

сегодня столкнулся с проблемой, что не могу создать учетную запись, используя домены от mail.ru. на скриншоте показал результат моих действий: я как обычно ввел почту, поставил пароль, заранее в самой mail почте разрешил использование imap, а когда нажал готово и разрешил доступ в самом thundebird, то окошко с входом просто закрывается и пишет "не могу войти на сервер", хотя я даже не ввел пароль. это происходит со всеми доменами типо inbox и т.д, с gmail все работает нормально. помогите пожалуйста

I have been using Thunderbird for years and have never had any problems; unfortunately, from few days, every time I try to download my mail, thunderbird starts downloading all my 15,000 emails, even though they have already been downloaded and read. I am desperate... I don't know what to do. Please help me... thanks!

Does anyone have correct server setting for Thunderbird so that I may access my optonline.net email account.

pmg

I'm trying to connect Thunderbird to my Mailcow server SOGo Calendar, but it does not work. It's not a typical problem, because SOGo generates for me two CalDAV links to connect this: 1. Link for signed in users (with RW access). 2. Public access link (with RO access). I want to manage my own calendar, so I need first case. Then I go to "Creating new calendar" window in thunderbird, enter public access link just to check, and calendar is connected! But it's not all. Then I go back and paste link number 1, also providing credentials info (I have tried a lot of variants, also "test@example.com:password", "test@example.com" and so on) and after pressing "Next" button I get a typical connect error like "Could not find your server, please check entered info".

I have done a lot of tests and checks, and this is a strange details, that I caught and I think it is a Thunderbird bug (I might be not right)... On my nginx reverse proxy I see such log when Thunderbird is trying to connect by my link with RW access: "my-ip-address - - [04/Jun/2025:23:39:51 +0300] "mail.example.com" "PROPFIND /SOGo/dav/test@example.com/Calendar/personal/ HTTP/1.1" 404 146 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:139.0) Gecko/20100101 Thunderbird/139.0.1" "-"". As you can see, my server returned 404 error.

You can think, that problem is on my side and my server is wrong, but please check next nginx log: "my-ip-address - test@example.com [04/Jun/2025:23:38:43 +0300] "mail.example.com" "PROPFIND /SOGo/dav/test@example.com/Calendar/personal/ HTTP/1.1" 207 125 "-" "curl/7.88.1" "-"". It is succeeded, but this is after my manual curl command like "curl -v -X PROPFIND "https://mail.example.com/SOGo/dav/test@example.com/Calendar/personal/"". You can compare two strings from nginx log that I provided and you will see the only difference is second dash in first log instead string "test@example.com" in second log. That piece of log string contains nginx variable $remote_user, and that means that Thunderbird while trying to connect my server calendar do not provide auth credentials and send request without any user that I enter to corresponding field before connect attempt.

P.S. You can ask me why do I test connection just by PROPFIND request type, because Thunderbird tries some different ways to connect too. And I will ask that: 1) Only one succeeded request, by what Thunderbird connects to my public calendar is with type PROPFIND (as I can see in nginx reverse proxy logs); 2) Other attempting ways to connect falls with same error and also do not contain any user, as I explained before.

Please give me feedback about way how I can fix that and thank you very much for your support!

Problem:

You remove an account like Google from Thunderbird, but Thunderbird continues to repeatedly show a pop-up to log into that account (in my case Google). I've noticed it even freezes the Thunderbird UI on startup.

Note: I'm self-answering this question. Mozilla Support has similar questions, but they're archived with incomplete answers. By archiving them, Mozilla is preventing the community from improving the solutions on those problems.

This exact question has been asked at least 4 different times, and it's been archived with 4 different solutions. All of them are valid advice.

• "Check your calendars" - https://support.mozilla.org/mk/questions/1441082
• "Check your addons" - https://support.mozilla.org/en-US/questions/1208183
• "Check your addressbook" - https://support.mozilla.org/en-US/questions/1440106
• "Check troubleshooting info" - https://support.mozilla.org/en-US/questions/1398233

Running Thunderbird 139.0.1 (64-bit) on new Windows 11 machine. Thunderbird is set as the default email client.

When I click on a mailto: link, it just brings up the Thunderbird application, but does not open a new message box.

My Windows 10 machine running 128.11.0esr (32-bit) handles it just fine. The OS app settings and registry settings look consistent on both machines.

As a test, from the command prompt, I run the command... Windows 11... "C:\Program Files\Mozilla Thunderbird\thunderbird.exe" -compose me@domain.com or Windows 10..."C:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe" -compose me@domain.com and it clearly shows the -compose argument is not being handled on the Windows 11 machine.

Before I uninstall the 64-bit version, is there something I am missing?

Hello all!

I use Thunderbird's desktop application for work. The problem that I'm having with Thunderbird is in regards to email composition. Every email defaults to plain text (new emails, replies, etc.) despite the following: settings > composition > sending format: "HTML only." I have restarted the application as well as my computer to allow for any setting changes to take effect.

I would prefer rich text or HTML, especially since my signature is in HTML format and it looks awful in plain text.

Please let me know what additional information I can provide. Thank you in advance for your help!

I am trying to send an email to a recipient of a previously SENT email keeping the originally SENT email with it. In now defunct Windows Live Mail emailing software, I use to click on "Reply All" and remove my sending name from the 'send to' address. Is there a similar function in Thunderbird?

My sent folder has stopped displaying the sent emails. This has happened in about the last 10 days. Before that is was displaying them perfectly ok. I've tried all the suggestions but they are ALL old , and there's nothing there that has helped me.

Thunderbird has started repeated prompting me for a security exception on a certificate supposedly issued by www.b-g.k12.ky.us (a site associated with my grandson's school system). This site is not one of my email servers. So why is Thunderbird complaining about its certificate?

For historical reasons that are intentional (forwarding at the ISP level) I regularly receive the same email into two of my email accounts (call them account A and account B). When I perform a global search only one of each pair of identical emails is listed.

If I delete the email that shows up, and then repeat the global search, the results now include the other copy of the email that was previously not displayed.

This proves that both copies have made it into the Gloda (the global index) but the filtering of the results is hiding duplicate emails.

If this is "works as intended", then I am happy with that, but I am curious about two things...

1. When account A and account B contain duplicate emails, it is somewhat random whether the one in account A or the one in account B is hidden. However, I rebuilt the global index yesterday, and after that, a global query with duplicate emails showed all the ones from account A and hid all the ones from account B. Today, after receiving more duplicate emails, the duplicates of today's emails in account B are displayed and those in account A are hidden. I am wondering what defines which gets hidden.

2. What is being checked to discover that two emails are identical? Looking at the message source I see that although the message bodies are identical, the headers are wildly different for the most part. Is it perhaps checking the "Message-ID:" line of the header?

When I try to send an email I receive this error message:

"Sending of the message failed. An error occurred while sending mail. The mail server <tlkramer52@sio.midco.net> sender rejected. AUP#BL. Please verify that your email address is correct in your account settings and try again".

I have verified that the address is correct. How can I fix this problem?

T. Kramer

I had to reinstall thunderbird. With all the correct information of settings from my internet carrier, I still can't send email. I can get them, I just can't send any. I get an error message that my server has timed out. I've already contacted my carrier and they couldn't help. I'm able to receive and send email directly using their webmail online site, but not with Thunderbird. Help! Nicole

Using Ubuntu 24.04.2

I have a large desktop made of 3 screens of different size, resolutions ans scaling factor.

When I open a message it get displayed with a stupid timestamp size on the most left screen

I tried with X-Randr and Wayland but still