Thunderbird Community Forum

Proszę o pomoc. W pracy na wifi program nie chce mi się połączyć z serwerem poczty. Jeśli połączę komputer z inną siecią wifi nie ma pproblemu program łączy się z serwerem poczty i bez problemu pobiera i wysyła pocztę

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.

Hi, When i start the TB-client on a win10 desctop there will be an Authentication error connecting to server imap.gmail.com.

from Google: 400. An error has occurred, The server cannot process the request because its format is incorrect. The request should not be made again. Unfortunately, we don't know more than that!

It still seems like the email arrives to the gmail account. But it turns out that the email doesn't always arrive via sync. Do you see any problems with the TB and gmail connection?

For the moment I don't know the Thunderbird version, I will be back.

TIA, /Leo

It was working fine on the new computer until yesterday. Now I get a pop-up box that says: ' Unable to connect The connection was refused when attempting to contact localhost.

The site could be temporarily unavailable or too busy. Try again in a few moments.

If you are unable to load any pages, check your computer's network connection. If your computer or network is protected by a firewall or proxy, make sure Thunderbird is permitted to access the web.

Hello, since 2 weeks the IMAP settings don't work. I didn't change anything with the accounts. Regularly I had to update the settings on my android version and it works well. But on my windows version ou on my linux version it doesn't work. I enter different name (the surname only, user name, or the mail address or name and surname). I tried all the options but it didin't word. I stopped trying last week on Thursday and tried again friday afternoon. I tried again several options and it works until saturday. Again I didn't change anything. I receive the notifications (in french) : "can't access the server outlook.office365.com" for the accounts. It was on my windows version AND on my linux version. I really don't know how I can fix it. I cleared the cache several times. Verified the server names. Today I serched for the settings on outlook for the IMAP server but didn't find how to change or disable it (the option were not visible on the setting page). I deleted the accounts to add them later but when the windows popup open even if I enter my password, and the code (if necessary) thunderbird send a message like "error. verify the id, username, address or password". I tried with the new thunderbird version on windows (because mine was old) - didn't work either. I don't know what to do or try now.

I have the android version and it works well, but this is on a secondary device and I absolutely need my mails on my main device and I really love using thunderbird. I even installed it on my kids devices. I really don't want to install another email client.... and absolutely not outlook T-T.... My thunderbird on linux is updated and didn't work too. But it's on my main device too, so if you can help me make it work on linux, I'll be happy ^-^.

I thought it was a connexion problem but even when I change it, it didn't work (on windows or linux).

Please can you help me fix this problem ?

Edit : Just wanted to add that the version on Linux (Mint) is the 140.12.0esr

I have four different email accounts. A week ago, all incoming and outgoing traffic suddenly stopped . Webmail works normally. I have no viruses, trojans, etc. I deleted one of the accounts and tried reinstalling it. I can't do it anymore. The system keeps responding: "Unable to authenticate to the server. Username or password configuration may be incorrect." But they are all abolutely correct. I don't know what else to do. Any clue? Thanks

[Edit:] I'm using Kubuntu with Thunderbird installed via flatpak using the flathub repo.

When attempting to add my calendars on our Nextcloud server, I can't get further then the second dialog.

Steps to reproduce: 1. New account > Calendar 2. Select "On the network" 3. Enter the correct user name and address (I did try the server address AND both CalDAV addresses presented in the calendar settings on the Nextcloud web app). 4. Press "Search for calendars" 5. After an extended period of time a dialog with a title "Adding a security exception" appears, claiming, that our Nextcloud site does not have a correct certificate (it does).

This is where the journey ends. If you add an exception, the dialog disappears and you are still at number 3. Trying again will produce the same result. Funny thing is, that you can press the button "Load certificate" in the "exception dialog" and then the same dialog will declare that our site does indeed have a correct certificate! But it will only allow you to close the dialog and you are still at number 3 and without any chance to add your calendars.

This is a completely new installation of Thunderbird. There are other folks that are using Thunderbird with their calendars on the same Nextcloud server and everything works happily. I presume this is a bug with the newer version of Thunderbird or something of that sort.

My BT Mail (premium account) stopped working in Thunderbird about a month ago. I've been using it for many years without a problem, so can't understand what has changed. I'm using it on a desktop with Windows 11.

I had a long session with a tech person from BT, who couldn't find anything wrong. All the IMAP settings are correct. I have removed the saved passwords in Thunderbird and changed them via the webmail platform. I have uninstalled the account and tried to reinstall it but it won't set up the account at all now.

It works perfectly on Webmail and on my iphone so it must be something to do with Thunderbird itself.

I have thousands of emails saved so any help would be appreciated.

I have been using Thunderbird email for years. Recently, I have gotten this error message: Connection to server mail.5starpros.com:465 failed. I have checked all the settings and they are right for my domain. I called the hosting service to check for email on their end and everything is fine. This message is blocking my domain at 5starpros.com. But, in Outlook on the same computer the same email address is working just fine. Thunderbird has the same settings and is getting my email. Is like my PC is blocking my email address. Can anyone help me with this. It is very distressing.

I keep getting prompt with this message stating the current config is set to block cookies (attached screenshot) and is occurring every interval. I had updated the app yesterday, some how after restarting the computer, it's popping up with the message.

I have been using Thunderbird for years. Suddenly, a couple of days ago, the sent and trash folders no longer show the emails in them. When I use Roundcube online, these files show up there as normal.

I have done considerable research online to solve this problem to no avail. Using AI, they suggest a number of things that I have tried, without solving the problem. Apparently, this is somewhat common. I finally got to deleting the send.msf and trash .msf. This did nothing to solve the problem.

This is very frustrating. What can I try next? I am using Win 11 and Version 152.

Carl

I have no idea why Thunderbird stopped working for me and I can't seem to solve the problem - one day. I got a notification to re set my credentials - nothing since

Hello,

Does anybody knows why or how this happened? Thunderbird has worked just fine since the May 1. My internet connection works well. Has anybody had this problem before?

Thanks

N DC

Hello, from time to time my Thunderbird on my desktop PC running windows 10 doesn't receive emails, while they arrived on my I Phone 8. Checked my Telstra web mail, all emails are there so what is stopping getting to my desktop PC? I thought the Thunderbird receives emails than synchronize with my I Phone? As you can see from my 2 images the Telstra is up to today as is my I phone But Thunderbird is 3 days beyond. Tomorrow it may back to normal or the next day? I am returning to this message the next day 16/06/2026 1 more message on my I Phone, still nothing on my Thunderbird.

An other problem I get with Thunderbird is that a message appears on the right bottom of my screen: "Mozilla Thunderbird Connection to server mail.bigpond.com timed out" and/or "failed to connect to mail server imap.telstra.com" If I try to send an email after the above notifications, I get the "Connection Refused". I know than to just walk away. I am using Starlink as Telstra here doesn't work as I am on the fringes of Melbourne in a BLACK HOLE. Any help will be gratefully received. Thank you for reading this. Regards Ilio Pieroni

I've successfully connected to a hosted Exchange server through EWS and NTLM authentication (kudos BTW). But there is a problem - often during operations against EWS I'm presented with "Login to account XXX failed" "Login to server YYY with account XXX failed". I can ignore it (cancel) and it will work for seconds or minutes but eventually reappear. Sometimes it's very frequent, sometimes is here and there. TL;DR; connection works, I can read directories and e-mails.

From looking at development tools I see these scenarios: 1. POST requests return 200 always (no messsage of course) 2. Eventually a POST would return 401. Then Thunderbird issues a GET, it returns 401 as well but response includes header WWW-Authenticate: NTLM XXXXXX. Then another GET is issued containing header "Authorization" with the value from previous response. This time it gets 200 and continues without POST requests without a dialog. 3. Sometimes there are more POST requests with 401 (I assume in parallel) before a GET is issued and then I see a dialog. Sometimes it recovers (regardless of whether I cancel or retry), sometimes gets stuck with 401 with dialog reappearing each time it tries something. This case it's similar in sense that thunderbird issues GET with 401 and WWW-Authenticate header, issues another GET with Authenticate header but still gets 401.

If I had to guess I'd say the problem happens when POST requests are issued in parallel, not sequentially. OTOH it might be a problem at the server, but it isn't very likely.

I have email accounts that are with Shaw (shaw.ca) which was bought by Rogers. I've had these accounts for years, and about a week ago the emails were not being downloaded and I could not send emails either. The email server is : Incoming - imap.shaw.ca, security type SSL, port 993

                   Outgoing - mail.shaw.ca, security type STARTTLS, port 587, with domain shaw.ca

I deleted Thunderbird and reinstalled it on my desktop computer that runs Windows 11, and attempted to add my Shaw email accounts using the above email server information, however received an error message that it could not connect to the server. I was however able to set up my Outlook and Hotmail accounts and could receive and send messages.

I also have Thunderbird on my laptop (Windows 11), and the Shaw email accounts were also unable to receive or send, although they were receiving and sending last week.

I contacted Shaw (Rogers) technical support and they said the Shaw webmail was operating because I could send and receive using Webmail, but that it must be an issue with Thunderbird. This did not make sense as I also installed Canary and Mailspring, and was unable to have my Shaw email accounts set up in those email programs with them being unable to connect to the Shaw email server. The tech rep said I would need to contact Thunderbird to have them confirm there was no problem on Thunderbird's side.

I also installed the Outlook email program and tried installing one of my Shaw email accounts using the Shaw server specs, and it installed the account and connected to the Shaw email server. I was able to send and receive emails from it. When I used the same Incoming and Outgoing specs in Thunderbird, Canary, and Mailspring, it would not connect to the Shaw email server.

Any suggestions as to what the problem might be and what might be done to correct it to allow my Shaw email accounts to be set up in Thunderbird would be much appreciated. Thanks.