Thunderbird Community Forum

On the 20, of October I was forced to re install Windows 10. Kept my data but I had to re install all my apps. With Thunderbird I follow the same procedure I used with Firefox: After installation I copied the profile folder from my backup and replaced the new one. That worked out well. With Thunderbird, I followed the same procedure, all my emails where there but not my local folders. I am attaching several snapshots to illustrate my steps. Image 1 "local folders now" Image 2 "Profile Folder". (why there are 2 sub-folders)? Image 3 "Mail in the profile folder" Image 4 " List of folders in my Local Folders" The are there, how do I get them back on Thunderbird in the correct place "Local Folders"? Thank you for your help again. Regards Ilio Pieroni

I can't find where to edit the rules that I previously created for what will happen when a certain mail comes to my mailbox. I set up a rule that marks a mail from a certain sender with "Important" and also sends a copy to another mail adress but now I can't edit the rule. Can someone help me with where I can find the rules and edit them?

I have to add a office365 accounts. Everthing works, until Microsoft's popup window requires to sign in to MS 365.

When I click in "Sign In", nothing happens. The button becomes light blue for some seconds, then turns back to blue again.

The credentials are correct, there is no error message, nothing.

Probably a problem with the popup browser window?

Javascript is enabled. Anything else that could break this?

TB 143.0.1 (aarch64), MacOS 15.6.1

I have have had a Gmail address for a few years and have just created a new Gmail address, I am trying to copy about 20,000 emails from the original Gmail IMAP folders to local Thunderbird folders as a backup, and then copy them to the new Gmail address IMAP folders.

I have tried copying these in smaller amounts as suggested (between 200 and 500 at once) This seems to go well, however, when I have completed the task the original folder has a much higher amount of messages in it than the new one, so some messages are being lost along the way.

Is there a reliable method to do this, such as closing Thunderbird and then copying and pasting data held in the profile folder, or does it need to be done with Thunderbird running?

Many Thanks in advance

Hi everyone,

I’ve run into a weird issue with Thunderbird on macOS 26 (Tahoe) and I’m wondering if anyone else has seen this.

When I close the main Thunderbird window using Command + W or RedDot Close Button, the window disappears like normal, but something is still left behind. It’s like an invisible or “ghost” window stays on the screen. Because of that, I can’t click anything that was underneath the Thunderbird window. The area is still blocked as if the window never fully closed.

If I open Mission Control (F3), I can see an empty tile where the window should be, which confirms that something is still there even though it’s not visible.

A few details: • The problem happens every time I close the main window with Command + W • Thunderbird keeps running in the background, but I can’t bring the window back unless I quit the app completely • This only happens with Thunderbird, no other app on macOS 26 has this issue on my machines • On previous macOS versions I never had this problem

System info: • macOS 26 (Tahoe), fully updated • Latest stable Thunderbird release • Mac mini M4 and MacBook Air M4

It looks like some kind of window management bug on macOS 26, but only triggered by Thunderbird.

Has anyone else experienced this or knows if it’s a known issue? Thanks!

I was trying to change the time emails are kept on the server so I went into "Account Settings" and now Thunderbird is locked onto this page. I get a "Mozilla Thunderbird not responding" message when I try and click on anything and I can't get out of this page nor access my Inbox. I've tried starting Thunderbird in Safe Mode which didn't work. I then uninstalled and reinstalled the latest version of Thunderbird but when it starts it goes straight back to the frozen "Account Settings" page. I've checked my profile and there is a new profile that was created with today's date. There is also a profile from June 2025. If the old profile contains all my emails and folders up to yesterday, that would be OK.

My gmail account in Thunderbird has only two folders, the Inbox and the Drafts folder. so when I delete a message, it lines out the message in the inbox with a single line strikeout and then in order to get it out of the Inbox I have to leave the Inbox and then when I come back to it the message is actually gone from the inbox. When I am using my laptop rather than my desktop computer, all of the folders are there and the messages, when deleted go to the "Trash" folder and are removed from the Inbox. I have been looking for a way to get all of those folders that are normally a part of the other accounts that I have on Thunderbird without success. Is there anyone here that knows how to restore those additional folders to the Gmail account that does not currently display them?

When replying and using inline comments, any backspace gets turned into a carriage return at the end of the message. If you backspace over the first letter of your reply it throws you to the end of the message.

W10 machine, Thunderbird 140.4.0esr (32-bit)

I thought I had successful auto install W-10 but when I open to send 1st message the"+ new message" button is not active/working. Per article this is how to start. Thanks for help.

When I compose email messages, I want them to be plain text only. In older versions of Thunderbird, this worked fairly well, but in new versions, even though the message is sent as plain text, it is not the same text that I type into the editor.

For example, if I begin a line with "> " (greater-than space) to indicate a quotation, Thunderbird will add another space at the beginning. I once tried to send "-- " (dash dash space, a signature marker) in a message, only to find that Thunderbird replaced the space with a non-breaking space.

I didn't ask for that. I want the content of the message that I send be exactly what I type, nothing more, nothing less. No reflowing, no subtle character alternation. Is there a setting to disable those mis-features?

I copied my profile because I had to reinstall TB. When I copied it back, I got all my emails but not my address books.. How can I get these back? Also, I got my emails back but it didn't include the number of each. How do i get these back?

To be clear, I seriously doubt the problems I am encountering are TB's fault! The problems may be my fault since I've grown older, I've tended (believed) using new versions of software present my mind a BIGGER challenge than using the older software/version I have been successfully using? I'm still using Version115.10.1

After our ISP chose to start using Zimbra Oct. 7, 2025 and their tech support could not assist me in getting TB working the had me remove POP3 settings for TB and change to IMAP with their software.

FINALLY someone helped me get TB working with IMAP. For 3 days grrr. Now the ISP says I need to use their web mail, Zimbra.

So might downloading the current TB version and somehow get the In box, all the folder contnets etc. over - into the new TB help?

I was going to backup everything tonight, now I have little to NO hope, without help!

THANKS & remain WELL plus be SAFE!

Robin

I've been searching for a few days for a solution to Yahoo Mail not downloading to Thunderbird, I've seen other people with the same problem, I've tried different solutions, but at this point I've given up. My Gmail is still downloading but I have to check my Yahoo Mail via a browser. What gives? Why did this happen in the first place?

I have Windows 11, I've updated Thunderbird.

Upgraded from Windows 10 to 11 a couple months ago. Since then, TB freezes nearly every time I am composing an email. "Help About" says TB is up to date. Remedies? Or do I have to wait for a new version?

Chris Sackett

Every time I want to print an email, the default copy number on my printer menu is shown as 2.

I don't know how, when or why this change [from 1 copy to 2 copies] happened.

I wish to 'reset' the default copy number to 1, so I don't accidentally print a second copy and waste ink, etc.

When I want to print documents stored on my PC, the copy number field on the printer menu is blank, allowing me to enter the number of copies I want - so the issue appears to occur only when I print emails.

Hi

I am using the latest TB build, 144.0.1and have only the British dictionary as an extension, no themes.

Occasionally TB will hang when launched and the Windows event viewer will show this....(added image)_

The friendly xml log within the event viewer...

AppName thunderbird.exe

 AppVersion 144.0.1.0 
 ProcessId 0x6234 
 StartTime 0x1dc51956edcf231 
 TerminationTime 5 
 ExeFileName C:\Program Files\Mozilla Thunderbird\thunderbird.exe 
 ReportId f3ad169f-c629-4357-85ae-7db29d0541f1 
 PackageFullName  
 PackageRelativeAppId  

HangType Cross-process

as noted, this only happens when the email client is launched and will not happen each time. I have tried without the dictionary, as it is so random it can take a while to occur, but that does not seem to make a difference.

I am using Windows 11 25h2

Thanks

I suddenly this week cannot send email using Thunderbird (v. 140.4.0esr (64-bit)). I receive email fine. I can send email using webmail with my provider. Error message in Thunderbird is: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-h2p-555359.sys.comcast.net resomta-h2p-555359.sys.comcast.net ESMTP server not available (62240/216.183.125.238)." My provider says the issue is not at their end because my server settings are correct. Outgoing SMTP port is 465, connection security SSL/TLS. Operating Windows 11 v. 24H2.