Yonke imikhiqizo Community Forum

I have a set of e-mails that I am unable to delete or move - when i try they disappear for a few seconds and then re-appear. They all contain a red bold warning "Caution external e-mail"

Hi folks. Been using Thunderbird for years now. Never had an issue till now. It recently began to check the spelling on EVERY email. Even if spelling was perfect. It never displays a misspelled word (I'm a good speller). Window comes up and despite hitting ignore it refuses to send. Only after you select Close will it send.

I've uninstalled it and did a fresh install. No luck. I did keep the old profile.

Hi all,

After thoroughly searching this database, I could not locate an answer to the issue I am facing, although there seem to have been several similar cases.

My former university has recently decided to delete alumni email accounts, so I am using Thunderbird for email transferring from university to GMail (added both accounts to Thunderbird and then began copying emails and folders). Transfer is slow, depending on the server capabilities etc., but I am going folder by folder and so far it has been fine. I began the transfers a week ago.

Last night I noticed my Thunderbird inbox for my school is not showing anymore. The profile folder is only showing one file (.msf) for Inbox, instead of what should be, in my understanding, two files.

Thunderbird is still communicating well with the university email server because I made a folder rearrangement on the university webmail service (outlook.com) and it showed on Thunderbird. In addition, all my Inbox emails appear fine on the university webmail service (outlook.com).

Any ideas? This is obviously important and urgent.

Thank you in advance.

I'm using Thunderbird 140.6.0esr (aarch64) on a 2024 14" MacBok Pro running MacOS 15.7.3 (24G419).

I manage fourteen email addresses, with most of the traffic going to one primary account, either by direct addressing or forwarders from others of the addresses. Maybe not the most efficient setup, but it means I don't have to scan 14 different inboxes to find the messages I most need.

I currently use ±89 filters on this primary account to file messages in a LOT of mailserver-based folders, and a few folders on the laptop. ±90% of the traffic gets filed in server-based folders so I can use any device to access message history. (I should probably note that these filters and message-threading don't always play nice together.)

For a long time, one of the message filters I'll call "Filter BS" successfully filed specific messages in "Folder BS," a server-based folder 2 levels below the inbox. Folder BS also has 2 levels of sub-folders within it for annual and monthly filing.

Some time ago, I began to have problems with messages of many kinds (subjects/sources/etc.) going missing. Eventually, I searched and found them in Folder BS. In response, I deleted Filter BS, looked for but didn't find other filters responsible for these unexpected results, and managed incoming BS-related messages manually. But despite Filter BS having been deleted, non-BS-related messages still get "lost," meaning incorrectly filed in Folder BS, which is acting like a rogue black hole, sucking up everything that gets too close. I have not been able to identify any criteria for what turns up in Folder BS beyond "lots of stuff that doesn't in any way belong there."

Speculating that something's "off" with the BS folder's directory in a way that would be nearly impossible to fix, I'm trying to figure out the least inconvenient, least risky way to solve the problem.

Not knowing other ways I might compound the problem by making big moves with the MANY messages archived in the BS folder's 7 annual subfolders and their 12 each subfolders; and not knowing how to back up server-based in-box sub-folders, I'm stuck at an impasse.

How should I proceed?

Thanks in advance for any input.

Dear community members, Since receiving the Thurderbird release 140.4.0esr on Oct 14th, I have not been able to send email from any of my accounts (2xIMAP and 3xoffice365 through OWL). Nothing has changed in the account settings. Receive works ok. The usual easy fixes do not seem to work (restart, firewall switch-off, etc.). Any ideas beyond having to rewind to an earlier version and rebuild the whole thing (hopefully not!)?

Version 140.4.0esr Build ID 20251010020716 User Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:140.0) Gecko/20100101 Thunderbird/140.4.0 OS Darwin 24.6.0 Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:30 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6020

Thank you for your help! Heli

When I let thunderbird compress the inbox and other folders, the not read flags on all new emails get reset as if I have read all of the new emails. Compressing the inbox and other folders should have no effect on the flags showing a message has not yet been read. That only makes sense. The not read flags getting reset started happening several versions before 145.

I was working with thunderbird today. Was in a specific email folder I had named "reference" that I use to store various emails, probably around 50 emails in there. Suddenly they all deleted from the folder as I was watching the screen. Checked spam/trash folders and nothing. Also logged into my webmail provider and nothing there either. Any idea what could have happened here? They just seem to have literally vanished. Have used Thunderbird a number of years and never experienced anything like this.

Hi, The question is in the title. I have imported my Outlook data in this 32-bits version (updated to 140.7) . I would like to keep them in a 64-bits version (147). I didn't find the solution. Thank you for helping me. Michael.

I am using TB 140.7.0esr(64bit) on a windows 11 desktop/ Starting 15 Jan at ~ 8pm, my outgoing SMTP email from multiple tds.net email accounts through my default server (tds.net) is failing with the following message: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Cannot connect to SMTP server 129.159.94.43 (129.159.94.43:587), connect error 10060." The outgoing SMTP configuration is: "Server name: mail.tds.net Port: 587 User name: john.randle Authentication Method: normal password Connection security: STARTTLS" I have not made any changes to that configuration. I am still able to send SMTP by switching to another email account/server (e.g. gmail.com). I have contacted tds.net and they say, not surprisingly, that it is an email client (thunderbird) issue. I am getting the same error on another desktop running windows 10 with TB 140.6.0 esr (32bit). Any suggestions will be appreciated. Thanks in advance.

I believe that version 145.0, newly installed on the 9th December, 2025 was showing server folders correctly; the server folder name matched the client folder name.

After upgrading to 146.0 on the 10th December, the server folder names for some folders are displaying with different client folder names.

The IMAP account has both "spam" and "junk" folders, Thunderbird is now displaying both as "Spam", you can only determine which folder is which by showing folder properties. It appears to users that there are two "Spam" folders now and not the two distinct folders with their own names.

Similar behaviour is happening for "Sent" and "Sent Messages" folders, both now display as "Sent".

These changes are confusing, the client sees two "Spam" folders and two "Sent" folders instead of the original proper server folder names.

Why has the display name for these folders changed?

How can I get TB to display the real underlying folder names?

Some senders for example Tangle go straight to my trash and if I move them to the inbox it immediately moves it back to trash. I do not understand what is blocking this nor how to do anything about it. Some send such as Erick Erickson generally go to inbox, but not always. Sometimes it goes to trash again.

Same Topic slightly different question... when I tell Thunderbird to delete all messages older than one year it does not do it. I do not know how to solve this problem. I do contribute to Thunderbird and thank you very much for any help that you can give. Don

What is the name of the element that corresponds to the background color of this message pane? This is a default background of a message window when I first open Thunderbird. I already have userChrome setup to modify other elements and I attempted to use the inspector tool to try to find the name of the message background color but I could not identify it. Please provide the name of the element in the form that I can use to add to my existing userChrome.css file to customize this black window pane.

Hi there! I and my colleague encounter some bugs with Thunderbird and we would like to seek your advice in regards of the issue.

1. <user a@citizen-systems.com.hk> was supposed to get a cc copy of the email sent by <user b@citizen-systems.com.hk> at Mon, 12 Jan 2026 09:35:19 +0800 but it never reached. The receivers, namely <user c@systems.citizen.co.jp> and <user d@citizen-systems.com.hk>, however, were able to get the mail. <user d@citizen-systems.com.hk> and <user a@citizen-systems.com.hk> are working at the same office and under the same network. Network provider checked the protocol, router, traffic and firewall are working as normal.

2. <user e@citizen-systems.com.hk> found a number of emails that she kept at "Inbox" disappeared on 12 Jan 2026 morning +0800.

She is unable to find it anywhere at her whole mailbox but has to ask the senders to resend them to her.

It would be very much appreciated if you can check and advise how to prevent the issue from happening again.

(PII redacted by moderator)

Hi, The question is in the title. I have imported my Outlook data in this 32-bits version (updated to 140.7) . I would like to keep them in a 64-bits version (147). I didn't find the solution. Thank you for helping me. Michael.