Thunderbird Community Forum

I recently got a notification that a Thunderbird update was available, so the update was downloaded and installed. Next I went to my inbox to tidy it up, by deleting some items and archiving some that I wanted to keep. On looking at the 2026 archive none of the items where found.

Why has this happened and is there any FIX ?

I need a filter on a message to FULLY FINISH before a next message starts to be filtered. The "help" (quotes because it's an abyssal crap) says that simply ending the filter with Stop Filter Execution does it - but that's simply NOT TRUE: calling a console program in the filter, I can see five DOS boxes opening at the same time with five messages matching, i.e. the filters on the next message DID NOT wait! So... what can I do??

All of the above is because I'm getting "Too many simultaneous connections on the server". I'd like to limit the concurrency, but it only seems to be possible in IMAP, while this connection is a POP. Why only IMAP??!

I'm running the current version of Thunderbird on Windows 11 Pro. Several time in the last few weeks I have noticed periods where I don't seem to be getting mail. When I close Thunderbird and restart it I get batches of 10-20 email messages that had been delivered to my shaw mail account, but which Thunderbird hd stopped downloading. There were no obvious messages that it had failed.

As in the subject, my computer has sound everywhere else but, despite 'play a sound' still showing as ticked in general settings, no sound happens when an e-mail arrives. And, in general settings for 'when a new message' arrives, I can hit the Play Button there and the sound happens. How do I fix this?

After the update, the 153.0.2esr program writes about an authentication error when connecting to imap.yandex.com. Please tell me what has changed and how to fix it.

I'm trying to set up Thunderbird to use for my email ([redacted] @icloud.com). I have an iCloud account and get my email with a browser going to iCloud but I don't know of a password specific to my email account. The password that I use for Apple iCloud does not work. What do I do? Thanks. Ed

My name is Barrie Johnson. I have been a Mozilla Thunderbird user for my e-mail services for many years. In the past couple of days I have been getting messages from Google telling me that my e-mail provider - i.e. Mozilla Thunderbird - will not allow Google to access it, with the result that I cannot get to a current version of my Inbox and there is no trace of my calendar details. Can you please help me?

The issue has been "An error occurred connecting to mail.mediacombb.net:993." on the server page, where you can "test connection to server" in Account > Server Settings > Security Settings. I get the same error message for each four different accounts. I have no problems with the other two different accounts not associated with Mediacom (MC). I contacted MC and they said my settings were correct and to contact TB. I have read several posts with no real solutions except that was resolved through an update. I plan to switch to a different Linux distro later. I am currently using Big Linux Manjaro with the latest update. Note that I had no problems with TB until last month. I do not do the uninstall/reinstall apps unless it will resolve my issues as a last resort. Second, sometimes I receive MC e-mails and did not run the "test connection to server," then until today while troubleshooting for several hours. I was trying to send out an e-mail, which I had no problems last week. I already went to Account > Server Settings > Advanced and changed the "Maximum number of server connections to cache" from 5 down to 1 with no luck.

  The e-mail server settings are:

imap.mediacombb.net 993 SSL/TLS Normal Password and smtp.mediacombb.net 587 STARTTLS Normal Password They have not been changed since I switched from windows 10 to Zorin 18 to currently Big Linux Manjaro. I attempted to locate a method to check if the server settings were correct via Terminal. M$ Outlook has a test page that you can send to yourself or another e-mail account. Last, MC tech informed me that M$ Outlook is more friendly than TB. I know that I have used M$ Outlook for years and rarely had any connection issues unlike TB. Unlike Evolution, which was my first after M$ Outlook, TB is much better and easier than Evolution. Thank you in advance for your time and advice.

Thunderbird had been working great for both of us until after my wife stopped checking her emails for a couple of months. When she later opened the program her inbox started downloading hundreds of emails (very slowly) until her inbox contained well over a thousand. I started to delete the unwanted ones but it went very very slowly. I finally whittled it down to a few hundred but the program continues to run very slowly in all phases. In one instance, it took 11 minutes to delete 39 messages. Downloading and sending are not much different. I've done virus scans, checked settings, restarted the computer etc., all to no avail. And when we switch users, my Thunderbird email runs perfectly. I also contacted my internet provider (Spectrum) but they said it had to be a program issue. How can I restore my wife's email to normal function? Thanks, Joe S.

I have had Thunderbird from the time I acquired my Mac computer. This week it started to do something new. After a restart I opened Thunderbird. A box came up that says across the top System Integration. The cursor balloons, and hasn't stopped for the time I powered the computer, as least fifteen minutes. You know how the program icons are in a dock across the bottom. With other browsers open, hitting the Thunderbird icon doesn't bring its window into the forefront. This needs either a reset, or possibly a backup first. Is there a quicker way to fix this? Thanks in advance. I am not using a VPN; but I also have Thunderbird on my Windows 11. You might have seen a more recent thread on that installation. I included a screenshot. It was easier here to do that than on the Windows 11. On the Mac, I just had to use Activity Monitor to close out of Thunderbird in order to get its version.

Hello,

Every now and then Thunderbird pops up the notification in the screenshot. Can anyone tell me what it means and if I should do anything about it?

Alan.

My Windows 11 was recently reinstalled to factory settings, which uninstalled Thunderbird but saved my mobx files. I used Thunderbird exclusively to view older emails that are stored on my PC as mobx files. I do not use Thunderbird as an active email client. I reinstalled Thunderbird, but have been unable to get it to find my mobx files that are stored together in a folder.

After updating to 153.0.1esr(aarch64). the SEND button has disappeared. There's no way to send an email. (I can receive emails.) I am a Mac mini M2 Pro. OS 26.4.1

I cannot find a link to download a previous release of Thuderbird, which was working fine until this update.

My account setting correctly are set to store send mail in send of the account. Now: - Shoud be: a send mail goes always there - Is A send mail goes sometimes to the local send folder

Pleas, tel me how to corect that.

Kind Regards, Ruud

I had this issue some while back, then an update resolved it. Seems another update has brought it back.

Having just updated, still on ESR, I find that I now have 2 folders named "Spam", but in fact looking at the folder properties 1 is actually still "Junk".

The images explain it well.

As in the past, I'm unable to correctly rename the second Spam folder back to Junk.

It has to be the update that caused it (as previously).

When can I expect another update to resolve it?

Hello - new forum user with some previous familiarity with Thunderbird. I'm looking for advice on mail import from Outlook (M365) on Mac OS. I will only be using TBird for accessing historical mails in future rather than as the main mail app going forward.

I have installed Thunderbird and looked at the Import Tool but it doesn't list Outlook as an option. I've looked through the Import Tool support pages and I can see Outlook is an import option but it only seems to appear when I filter the web page based on Windows 11 rather than Mac OS.

Am I able to use the Import Tool on Mac OS with Outlook?

I'm using Mac OS Monterey 12.7.6 and have Thunderbird 153.0.1 and Outlook for Mac 16.89 (M365) installed.

If the Import Tool isn't available, is the next best option to drag individual folders from Outlook to the Mac desktop to create MBOX folders and then drag those into Thunderbird?

Thank you in advance.

Environment:

• Thunderbird 153.0.2 (aarch64)
• MacBook Air, M4, Tahoe 26.5.1

When I try to create or rename an Inbox subfolder in Thunderbird it all seems’’ to work (no error message), but after pressing “Rename” or Create” nothing happens.

Thought I found a workaround: Created a “Temporary” subfolder in “Local Folders” and “moved it" to the Inbox. And it showed up there. (But it was still in the “Local Folders”!). Tried moving a (Spam) email into the Temporary folder under the Local Folders, that worked. Tried moving a (Spam) email into the Temporary folder under the Inbox—it just disappeared! It was no longer in the Spam folder, but did not end up in (either) Temporary folder.