Thunderbird Community Forum

Subfolders within a saves subfolder have disappeared! They contain important information and emails. I need them back. How do I get them back? In 2025? On a Mac computer?

I am experiencing a severe problem with Thunderbird. There are several symptoms: 1) The CPU utilization of Thunderbird is typically 13-19%. 2) Thunderbird declares that it was able to send a message and to save it, but that it experienced difficulty when running filters. 3) Thunderbird is unable to compact a folder. The message received is:

   The folder 'Inbox on william.atwood@concordia.ca' could not be compacted because writing to folder failed.  Verify that you have enough disk space, and that you have write privileges to the file system, then try again.

4) Thunderbird occasionally gives the following error message: Your message was sent but a copy was not placed in your sent folder (Sent) due to network or file access errors. You can retry or save the message locally to Local Folders/Sent-william.atwood@concordia.ca.

These are the symptoms that I see today. Over the longer term, I saw the following:

1) Thunderbird started to behave strangely several weeks ago. It somehow lost track of what messages it had downloaded, so it started downloading all of the message headers in my inboxes (and other folders). (I have six email accounts that I monitor.)

2) Since all of my accounts are IMAP accounts, with the messages stored on the server, I tried replacing the Thunderbird profile with a copy that I had previously backed up. This seemed to solve the problem for a short time. However, the symptoms soon re-appeared, including high CPU utilization, inability to compact folders, and difficulty running filters.

3) At the suggestion of my employer's help desk, I removed and re-installed Thunderbird. This found the existing Thunderbird profile, and everything seemed to work just fine for a few days. Then, suddenly, everything went haywire, and Thunderbird started re-loading all of the message headers for *all* of my folders (and for all of the accounts), and complaining about inability to run filters or compact folders.

Finally, Thunderbird crashed today. I added notes to the crash report, giving some of the details above. After it restarted, it crashed again. I finally ended up restarting my computer.

Thunderbird version 140.0.1 Windows 11 Edition Windows 11 Enterprise Version 24H2 Installed on ‎2025-‎04-‎30 OS build 26100.4349 Experience Windows Feature Experience Pack 1000.26100.107.0

What can I do to mitigate this problem? It is very difficult to use Thunderbird when it acts like this.

Bill Atwood

Hi,

Just upgraded to 140.0.1 and when I restarted Thunderbird it asked that I create a new profile, as if it was the first time I used it. I checked in %APPDATA%/Thunderbird/Profiles, I have 2 folders, one ends with .default (47 b), the other one, ends with .default-release (around 7Gb). I've tried messing a bit with the profiles.ini and the install.ini files but it didn't change anything appart from creating other 47b folders when restarting Thunderbird. So I'm back to the original files but I'm stuck. When I open the about:profiles page, the .default-release one does appear at the top and seems to be the default one, yet nothing shows up in the usual window.

What should I do?

Thanks a lot

Hello, I've come across a rather strange problem. I have a phplist mailing list (on domain1). When sending emails, I usually also add an image (as a link to the image). Since the beginning of June, however, I've noticed that Thunderbird doesn't display the images added in this way. Instead of the image, it displays an empty frame (a completely empty frame without any tags). Even if "Allow remote content in messages" is checked in the settings. Other email clients (outlook, gmail, roundcube) have no problems and display images without any problems. However, if I put the image on another domain (domain2) and put a link to this image in the email, Thunderbird also displays it. So: it doesn't display the image from domain1, where I have the mailing list, but it displays the same image from domain2 (in the same email from the same mailing list from domain1). Is it possible that Thunderbird is blocking the display of images from a certain domain?

The new version that was just installed immediately times out when I attempt to send an e-mail. I suspect there is an issue with my server as previously the first email I would try to send after a restart would fail with a request to check a security exception. Once I indicated to ignore the security issue, subsequent e-mails went immediately.

I keep installing the Add-on to customize the message body toolbar. Unfortunately, the toolbar returns after a while. Now I can't seem to find the Add-on to customize it.

Any ideas? James

When I double click on an email in my inbox, a new reply email is being displayed with a yellow message across the bottom saying:

   "A unique identity matching the From address was not found. The message will be sent using the current From field and settings from identity XXXXXXXXXX."

This happens only on my default account.

What can I do to get the email opened in a new tab as a default? See the attached context menus

Thunderbird: 140.0.1 (64-bit) Windows 11 Pro

Hi Folks. Todays date 21/07/2025 Since 17/07/2025 I've been getting a error message. Unable to write the email to the mailbox . Make sure the file system allows you to write privileges , and you have enough disk space to copy the mailbox. I've gone into settings and cleared the cache ( that didn't help ) I've uninstalled thunderbird and re installed ( that didn't help ) . What else can I try ? Thank you

This behavior started suddenly today. Every time I quit Thunderbird (by selecting "Quit Thunderbird" from the drop down menu) the program appears to close normally, but about a second or two later I get a pop up saying "thunderbird quit unexpectedly". Happens every time I close the application. Otherwise everything seems to be working fine within the program itself. I checked for crash logs, there are none. I tried running in Troubleshoot Mode, same behavior.

Any ideas? Maybe just a fresh re-install?

I keep getting a pop up when opening my mail that reads, "The folder on inbox (then gives my email address) could not be compacted because writing to folder failed. Verify that you have enough disk space and that you have write privileges to the file system and then try again".

I don't understand!!!

The subject says it all. I am expecting to see a link to page(s) that describe how to create an account and supply the necessary details. I managed to create an account for outlook, but can't repeat the process for AOL/verizon for what eve reason,

-m

Over the last month or so I've been been getting a lot of junk which is timestamped with future dates - like 2066 for example. Presumably this is done to promote the message to the 'front' of my inbox. Unfortunately there are now so many of these that I risk overlooking more important mail. Is there any way of filtering out 'impossible' dates I wonder? Any help would be gratefully received! Robin.

Hello I need help. When I automatically add an MS work account as Exchange, I can send emails but not receive them. However, when I select IMAP, I can receive emails but not send them (I get a message that logging in to the server using my username failed). My private MS account is configured correctly by default, and everything works fine (at first place).

ver 140.0.1esr x64

Hi all.

Previously, when moving to a new computer (Windows 11) with Thunderbird, I would install a new instance of Thunderbird on the new computer and run it once. This created the default Thunderbird profile in the Profiles directory. I would then copy the contents of the existing Thunderbird profile into the new one. This allowed Thunderbird to be fully operational with all accounts and filters working, requiring no further setup.

In version 140, I have followed the same process. While I do see all of the email accounts, they are not functioning.

Any advice on how to do a migration with Thunderbird 140 version?

Help!

I'm getting constant pop-up notifications for an event on my Gmail calendar, and I can't dismiss or snooze them. I tried deleting the event via my iPhone calendar, where the event was originally created.

It's driving me crazy. I just switched to Thunderbird from Outlook, and I'm ready to abort mission. I can't use Thunderbird if it is going to send me reminders for orphaned or corrupted calendar events I can't dismiss constantly.

Please help!

Here is the error message:

Error Code: MODIFICATION_FAILED

Status Code: 2,147,500,037, null

Server Replied with 400 If you're seeing this message after snoozing or dismissing a reminder and this is for a calendar you do not want to add or edit events for, you can mark this calendar as read-only to avoid such experience in future. To do so, get to the calendar properties by right-clicking on this calendar in the list in the calendar or task view.

I have visual issues and cannot read thin text. I am trying to set up a Windows machine where it defaults to thin text. Yes, both Windows and Thunderbird allow users to increase font size and scaling, but I don't have enough screen size. It's much more helpful to increase font weight, and only somewhat increase some font sizes.

I already have /* Global UI font */

• { font-family: Andika !important; }
• { font-size: 12pt !important; }
• {font-weight: bolder !important;}

Which makes the message list good and bold, and

1. threadTree tr[data-properties~="unread"] {

color: red !important; }

Which distinguishes unread messages.

But for whatever reason, the fix doesn't extend to the messages or the settings page.

I have a windows 11 desktop and Thunderbird 140.0.1 (64-bit) loaded. I have two email accounts. One is an AOL account and works perfectly on Thunderbird. The second account is Gmail which was working fine but at the end of May it stopped working on Thunderbird, usually with a timeout error message. I ended up deleting the account and tried to add it back into Thunderbird. When I try it won't add it. Thunderbird spends 3-4 minutes checking password and then gives me an error message that the configuration, password, or email must be wrong (see picture). But the email and password are correct and work every day. The configuration is IMAP, SSL and has the correct goggle addresses and ports. I have tried both OAuth2 and Normal password but still get the same issue. I have deleted the Gmail saved passwords, will allow cookies and my Gmail account allows IMAP. Help Please!

My copy of Thunderbird seems to be suffering from an email hijacking problem that seems to have be creating message reception delays. Has anyone else happened to have that problem or knows how to get rid of it?