Thunderbird Community Forum

I'm running Thunderbird 140.5.0esr (64-bit) on Windows 11 Pro.

I've been using Thunderbird for years, and I've had it connected to my Google Calendars since Lightning added support for it (and before that, used an extension to do it). A few weeks ago, I noticed that none of my Google calendar entries were present. They're just gone, even though they're all listed in Thunderbird and none are hidden. I'm not sure when they first disappeared, so I don't know if it corresponds with a version update (I was using 140.4.0 when I noticed. 140.5.0 didn't fix it).

I tried to re-synchronize the calendars, and nothing appeared, but there were no indications of any errors (nor any indication that there was any update activity occurring).

So then I deleted my calendars, deleted the account authorization info from Thunderbird, shut Thunderbird down, reopened it, and reconnected with Google from scratch. That logged in successfully and let me select which calendars I wanted to subscribe to, but once again, none of their contents are there. Nothing in the past or future.

Is Thunderbird's Google Calendar integration completely broken in v140, or is something corrupted in my Thunderbird install? If the latter, is there some residual file in my profile I should delete after deleting my Google account from Thunderbird, in order to reset this and get it working again?

Edit: I should add that I did check on Google's "syncselect" page for my account to confirm that my calendars are still available for sync. Nothing has changed here since it was last working in Thunderbird.

I've got 2 PC, both on the same version of W11 Home and TB?

On my PC that was install in 2020, I can see on each folder and sub-folder unread mail, total mail, and size of that folder (see uploaded image). On my wife's PC, installed in March of this year, only can show the total mail and folder size?

I've Googled how to do that and of course there is no such steps I can do?

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To show the unread message count in Thunderbird's folder pane, click the three dots icon ( ...) at the top right of the folder pane header and select "Folder Pane Columns" or "Show total message count". Some versions may also allow you to enable this view by right-clicking on the folder pane header and selecting "Folder Pane Columns," then choosing to show "Total" and "Unread".

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Right off the bat, no "Folder Pane Columns"???

I suspect somehow this was removed from TB, so new installs this year can't get to it?

I can't even get to that on my PC from 2020 to turn them off?

Is/was there another way? Doesn't seem I have an ADD-ON to do that and I can't locate one that would do it?

Is there an answer to this or is this just the way it is (not)?

Dear Thunderbird Community,

I cannot send emails from Thunderbird with the settings provided by my Internet provider (Spectrum). We've established that the web version of Spectrum.net works as expected. Also, I can receive messages with my Thunderbird. However, I cannot send any messages.

I am using the settings that Spectrum gave me, and they are also working correctly with my Android device, iPad and Outlook. I can receive and send messages successfully.

I have allowed Thunderbird to pass through my Windows Defender Firewall.

When the settings are not exactly what Spectrum tells me, this is the error I get:

An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: p-impout007.msg.pkvw.co.charter.net cmsmtp 179.61.150.63 blocked. Please see https://www.spectrum.net/support/internet/understanding-email-error-codes for more information. AUP#Out-1130.

When my outgoing server settings are exactly what Spectrum tells me, I get another error message:

Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) mail.twc.com timed out. Try again.

I'm not sure what else I can do at this point? Can I increase the length of time so that the connection doesn't time out?

Thanks,

Mike

Hello,

I had a TB crash, and clicked "OK" to submit the crash data before realizing all the "include data" options already checked.

How can I get Mozilla to remove this crash data from their site?

Thank you.

My preferred settings for the message list pane (not sure if that's what everyone else calls it) include unthreaded, newest at top.

From time to time, Thunderbird apparently forgets these settings, and in all my mailboxes and sub-folders, lists messages with the newest at the bottom and threaded. I haven't checked how often this happens and it doesn't seem to be related to updates.

Any ideas about why T-bird does this, or even better, whether and how it can be fixed?

I have Thunderbird 145.0 (64-bit) running on an uptodate installation of Windows 11 and have recently found that the email in folders do not always order themselves in the way they are supposed to. Although I have all my folders set to show emails in date order, with the newest at the top I am now sometimes finding new emails halfway down the list. This has happened several times in the last few weeks. I have "repaired" the folders every time I notice this but it has not solved the problem. Is there a glitch in the later versions of Thunderbird which is causing this? It was apparent today with my 'deleted' folder. I can't send you an image because I have now sorted the issue, until it happens again. I only discovered this by mikssing a couple of important emails and finding them in webmail but not in Thunrderbird. I use IMAP and my settings to the server are correct.

This is regarding TB 91.13.1 on Windows 11. I know with later versions of TB you can change a setting in Preferences > config editor to make the scrollbar wider. But this doesn't work with TB 91.13.1. In fact you have to add that preference, which I've done, along with several others. So far nothing makes any difference.

I've also added the text as mentioned here but it made no difference. https://support.mozilla.org/en-US/questions/1251403

Any suggestions would be appreciated, Thanks

i have always used thunderbird and am now up to 64 bit thunderbird 144.0.1 on windows 11 25h2

everytime i am sent a pdf file as an attachment i'm having to get thunderbird to open the file before i can actually save it to disc

everything else, while asking me for a name & location to save the file simply doesn't

btw thunderbird is now configured to ask me what to do with the pdf file and it ALWAYS behaves the same

i don't want to have to open files like pdf's that may not be safe / virus free before being able to handle them

way passed the time you fixed this stupidity terry

I have Thunderbird 140.5.0 installed. It keeps moving my mail folders. I had them sorted in alphabetical order but a week ago it started moving my folders. For example, I have a folder named "FunWithTubes" but it keeps moving to the bottom of the list after "Y" and if I move it back then a day or so later it will be back somewhere else near the bottom. This is not the only folder it does this too but does not do it to all of them. How do I get it to put my folders back where I had them and leave them alone? This has got to be a bug.

Thank you.

I cannot send emails and always get the same error message, no matter what steps I have taken. This has been the situation for nearly 48 hours. During this time I have undertaken the following steps, as advised by Thunderbird (TB)/ Optus and Google (not in order).

Checked SMTP server settings (many times), Re-booted the Router, Uninstalled and reinstalled TB, Changed the number of Server Connections to Cache from 5, down to 1 (as suggested by the TB Notification), Tried sending a test message to my other email address on several occasions, but got the same error message. I have checked my Webmail account and can send and receive from and to my email accounts from within webmail.

As required in the TB help file, The following information is provided: SMTP settings (attached). Mail Provider is Optusnet. ISP is Firefox. Antivirus is Trend Micro Maximum Security Version 17.9. OS (details attached).

If I have neglected any required info please ask. Any assistance would be greatly appreciated.

Thank you. Flin

Two nights ago I uninstalled ExpressVPN from my system at the instruction of one of their "support" people. My computer immediately lost the ability to access half of the websites I tried to visit and Thunderbird wouldn't send or receive email. I rebooted and that fixed every issue, but since then, Thunderbird no longer checks for new messages for any of my accounts. If I manually instruct it to check, it downloads the messages with no problem. I don't use any add-ons, and I'm using the latest version on a Windows 11 PC. I have already tried deleting global-messages-db.sqlite, repairing each mail folder from within Thunderbird, clearing the cache, and running an install of the latest version. I have also tried changing the setting for each mail folder to alter the interval for message checks by a minute just to see if that would jog it, but no luck. I've looked at various other help threads for this and am out of ideas. Thanks in advance for any help.

I have an existing account, I'll call it account1@rogers.com.

I wish to add a second account2@rogers.com.

The creation works fine but all of the subfolders of account1 and their content are duplicated under the new account2.

I use the auto configure option of Thunderbird to create this new account.

I wanted to create a calendar event from a message. My purpose was to have a reminder and have the information that was in the message.

I knew this could be done, because I had stumbled on to it before, but I could not remember how I did it.

Again I stumbled on to the procedure. You right click on the message. Select Organize / Convert To and then select Event or Task.

This information should be in Help. I am sure I am not the only one that would like to use this option.

Drag and Drop attachments to the desktop stopped working again with Thunderbird 145. Steps to reproduce: You receive a mail with an attachment. You drag an attached file from this message and drop it onto the desktop of your Mac to download it. The attached file is not saved to the desktop (or any other folder I tried). This is on MacOS 26.1 MacMini M4. Please fix asap.

So I have a self hosted Exchange and I have no problems using it from apps like Google Mail, Outlook and such, plus I can login directly to its .../EWS/Exchange.asmx through a browser. However, when trying with Thunderbird 145/Linux, I always get that username or password are incorrect, but it doesn't tell me exactly what went wrong and how it tried, so I'm in the dark why it is happening. Note: exchange's url is on a different domain than my account.

Basically it's either this message: Authentication error.

Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIMsgAccountManager.createIncomingServer]

Or similar if I try to get message from inbox.

Also weird things happen during configuration, like attached image (note that I've tried different URL permutations)

TLDR; how do I diagnose the issue, or ever better, how to connect? TIA

My Thunderbird mail, which has been set up as POP until now, started giving this message yesterday morning: "The connection to the server mail.munkebo-borger.dk was reset." After that, it no longer downloaded any mail from the server. I have now switched Thunderbird to IMAP, and everything works fine since then. But what is the reason that it will no longer run POP, which it has done for several years? Best regards Tommy Jeppesen

Thunderbird was sending and receiving just fine until a couple hours ago. Now, I cannot send anything to anyone - including my email provider. The message is: "Outgoing server (SMTP) error. The server responded: (C18) RBL restriction: Blacklisted by Internal Reputation Service" I verified all the settings (though I changed nothing prior to the problem) and all is correct. I've checked with tech' support and they verified that my address does not have a Blacklist. I've restarted the program and restarted the computer. I've also donated several times to Thunderbird. Before I change clients, I thought I'd see if anyone had a fix for this. Thanks, D

PDF filter doesn't work

Trying to refine my search to get only emails with PDF files attachment, only get an empty list when mails with PDF are in the base for sure.

Step by step with screenshots here attached sorted by A, B, C.

A - Basic search with "pdf"

     => 480 attachments files in emails 

B - Filtering A search to get only mails from year 2025

     => in 2025 only 27 emails with attachment - We see in the list result some emails with PDF files attached to it.

C - Trying to get only emails with PDF types attachment, clicking on the top left filter get nothing

      => It's a bug i guess.

Ubuntu 24.04.3 LTS Thunderbird 140.4.0esr (64 bits)

On 18 November 2025

the new beta mozilla has not copied my folder inbox folders, all past emails are gone. I want to revert back to the old system but it wont allow, and I have tried to import the old folders but that has not worked, all it has done is create 2 more copies of local folders (twice). Please help as the old emails are important.