I-Thunderbird Community Forum

1. Some messages come to my mobile devices but not to my Mac. 2. I watch a message down load but it doesn't end up in my inbox or junk folder. 3. Junk folder says there are 14 messages in it, but when I open it, it's empty. 4. Yes, I'm up to date with Thunderbird. Also, the Mac is up to date. Problem began before latest updates. I have shut down the Mac. I have quit the Thunderbird application. No improvement. 5. I use Comcast for my ISP.

Since the 26th of Feb. my thunderbird stopped downloading emails from any of my GMail accounts. I've accessed the email and i have a bunch of new emails there but for some reason they are not transferred to thunderbird anymore. I'm think i've installed a new thunderbird version around that time but im not really sure if that was the cause.

Also, no error message appears. it just says no new emails.

Already cleared the login details and logged again, still same issue. I'm using pop connection.

today, when I clicked on the Thunderbird icon (on my desktop PC), instead of my usual window popping up, an odd looking window came up instead that asked to sign into my account using my username, email address or mobile number. But when I tried (several times), none of them were recognised and now I can't access any of my emails because now when I try I get a message that says "Edge: Too many requests" ... this is followed by a pop-up window (bottom right), that says, "Authentication Failure while connecting to server imap.aol.com. This in turn is followed by another Crash Report window (attached screenshot).

I tried uninstalling Thunderbird, deleting cookies, etc, then reinstalling ... but no change.

First-time round I though the problem was Gmail - hotmail and my ionos webmail seemed OK

MS CoPilot ran a significant "tweak this" process over a couple of days but it was ineffective so remove and replace was applied. It was a hassle but seemed to work, but today problems are reappearing.

A Reply-to does not find the reply address but conncocts one - basically the "From" address. The resulting email does not have the usual header nor any space to insert text. The sent reply does not end up in Sent but does sit in Inbox

I am a club secretary. I want to send a small (under 100KB) Word document, as an attachment, to my committee mailing list of 7 people, which includes myself. I cannot get Thunderbird to do this. I can send the same attachment to just myself (or just my wife) but it seems that when I put multiple addresses, either as a mailing list or individually entered, the email isn't received by anyone. There is always a copy in my sent folder. I am getting very frustrated by this and would appreciate some help. Many thanks, Alan

Dears since yesterday i cannot download yahoo mails to thunderbird on my windows computer. when thunderbird gets new messages, a window pops up asking me for yahoo account name and password. when entered yahoo gives the following message: " Something went wrong. We could not sign you in. Try again from a different device." i use thunderbird 148.0 on windows 11 (out of china, with Astrill VPN - all other websites work normally with VPN). i have three different yahoo accounts, the first time thunderbird asked yahoo first mail and authentification went through, but it does not go through for the remaining two accounts. i verified that OAuth2 is set up for all accounts. password is correct (as i can still receive emails on iphone mail app). cookies can be accepted without any exceptions, can see the whole OAuth2 dialog panel. i did all steps for setting multiple accounts. i verified all accounts for POP and STMP server settings. also mailnews.oauth.usePrivateBrowser set to TRUE. After all this, it still does not work (i also restarted thunderbird and the computer), what else can i do? Regards Violaine

I have both a Microsoft 365 email account and a outlook.com email accounts. I'm using version 148.0. Both account set up just fine. When I delete an email from either account after a couple of seconds I get a message saying "The current operation on 'Inbox' did not succeed. The mail server for "the account name" responded; [TRYCREATE] The destination mailbox could..." that all I can read. Why?? It is only on the Outlook accounts. I have several other account set up and they all delete the emails.

Connection to pop.mail.yahoo.com times out and no emails are downloaded. A new windows appears from https://login.yahoo.com/ that I have never seen before asking for username and password but this returns a "something went wrong" error. Is there an update, or a setting change, that resolves this problem?

Thanks

Frank

Hi everyone! Why do I get an error when I try to download messages - "Failed to save message. Check the spelling of the file name, wait a while, and try again"

And the most annoying thing is that after this error, downloading other letters stops and you have to manually search for that very letter, although there may be thousands of them... Please fix this!

I have been using Mozilla Thunderbird for decades and they have even contributed a small amount of money to Thunderbird periodically. Just within the last two or three days all of a sudden I have been unable to send emails with my phone. I receive emails, but I do not send them.

So I opened up a laptop where I did not have Thunderbird and set it up properly through Spectrum using the incoming and outgoing servers as mail.twc.com. and yes, just like on my phone. I continue to receive new emails, but even with the laptop I was unable to send an email.

I received the message"send message error sending a message failed. The message could not be sent because the connection to outgoing server smtp mail.twc.com was lost in the middle of the transaction. Try again."

I contacted Spectrum twice and both times they had me try to send a message through their Web server spectrum.net and that message did go through. Of course then their response is that this has to be a problem with the third-party app meaning Mozilla Thunderbird, and they can’t help with that at all. I sure would appreciate some help because I hate to walk away from Thunderbird as well as change my email address after all of these decades.

Edition Windows 10 IoT Enterprise LTSC Version 21H2 Installiert am ‎18.‎09.‎2025 Betriebssystembuild 19044.6937

Thunderbird Version 148.0 von Feb 2026

bis zum 5.3.2026 funktoinierte TB einwandfrei, aber seit gestern kann ich keine Mails mehr versenden, folgende Fehlermeldung wird angezeigt siehe Bild Hochgeladen. Gestern wurde die IP 18.195.155.157 angezeigt, heute 3.70.126.251

Empfangen von E-Mails hat funktioniert nur beim Senden oder Weiterleiten kommt die Fehlermeldung.

es Spielt auch keine Rolle von welchem Konto ich Mails verfasse, ob T-online,Web oder Agenturserver

Benutze den Acount auch auf einem Laptop mit W11, dort funktioniert alles,

Die SMTP Einstellungen hab ich überprüft, Laptop und diesem PC sind identisch (Hatte ja auch keine Änderung in diesem Bereich durchgeführt)

Возникает ошибка:

Ошибка отправления сообщения. Сообщение не может быть отправлено, так как не удалось установить соединение с Сервером исходящей почты (SMTP) «smtp.gmail.com». Сервер может быть недоступен или отказывать в соединении по SMTP. Убедитесь, что указали корректные параметры Сервера исходящей почты (SMTP) и попробуйте снова.

More often than it should happen, when I try to reply to a message, TB opens a screen that is surrounded by a thick white line and I can't type in the field. Why? How to I fix it?

It appears how TB handles IMAP connections for outlook email accounts no longer works - OAuth2 connection flow broken, and this is likely due to stricter changes made on Microsoft's backend that is impacting connections going forward.

I have multiple email accounts configured and recently, I have been bombarded by login pop up - likely related to the OAuth2 authentic process.

Whilst I was able to circumvent the authentication process - i.e. not completing the flow process entirely as it expected, newly created outlook accounts appear to reveal two things:

1] There has been a recent change to the authentication process - i.e. the telling sign.

2] There is a now deeper issue when trying to connect outlook email accounts. It seems the reason why circumvention was possible with existing accounts was because they have already passed the OAuth2 process correctly - correct tokens exist. Since this won't be the case for new outlook accounts - no OAuth IMAP access token created, above error is given.

It seems the likely cause is because Thunderbird holds or requests a token that does not contain the correct IMAP audience/scope combination, and Exchange rejects it during SASL XOAUTH2 bind.

For your information, I am using the latest versions and able to configure Apple Mail client - which uses Exchange protocol (not IMAP), without issues.

Can not send emails to a newly created outlook.com (free) account. Have tried dozens of different settings, approaches.

My current setup:

 - windows 10
 - thunderbird 140.8.0esr (64-bit),  numerous previous versions also do not work
 - outlook.com (free) account mail provider
 - POP3 enabled (tried IMAP enabling also) on outlook.com account
 - no 2FA or 2FA enabled on outlook.com account, no difference
 - outlook.com web access works fine
 - followed instructions in mozilla support article Microsoft OAuth Authentication and Thunderbird in 2024 
      (https://support.mozilla.org/en-US/kb/microsoft-oauth-authentication-and-thunderbird-202)
 - have done a fresh install on a new machine without an existing profile.
 - have tried various microsoft servers, have tried oauth2, normal password
 - thunderbird account creation works just fine.
 - server settings and SMTP settings match as recommended by support article noted above
    SMTP server settings
        server name: smtp-mail.outlook.com  
        port: 587
        connection: STARTTLS
        authentication: OAUTH2
        user:  xxxxxxxx@outlook.com

symptoms:

 - receiving(downloading) emails works fine.
 - sending emails fails with following messages
     Login to server smtp-mail.outlook.com with username  xxxxxx@outlook.com    failed    followed by 
           Unable to authenticate to Outgoing server (SMTP) . Please check the password and verify the 
             'Authentication method' in 'Account Settings | Outgoing server (SMTP)'

Many people seem to be having this issue with no resolution.

Please help.

Добрый день! В течение последних двух месяцев периодически пропадает возможность отправлять письма с моей учётной записи на gmail.com. Во вложении скан сообщения. Приём писем стабилен.

На учётной записи ya.ru этой проблемы нет

Good afternoon.

When I receive emails such as password resets, or email verifications, etc., they always contain a line such as "click the link to verify your email", and they never display correctly like they do in other email programs, and I have to literally copy and paste the link in a web browser manually.

Is there a setting somewhere that I am missing?

Created new yahoo mail IMAP (PKCE) account using Thunderbird account creation. All seemed to work well. However, new account does not receive mail from "some" other IMAP and POP accounts in testing, including from TB Pro. Strangely, mail sent from oldest POP accounts works. Mail from newer POP gmail and TBPro accounts is not received. TB 149.0b1 Windows 11