Thunderbird Community Forum

The Inbox on my Thunderbird emails shows 224 messages but do not open. I have tried opening and deleting but to no avail.

IMPORTANTLY I am still receiving new emails.

When i minimize, it starts "eating" ram the computer crashed when it consumed 59GB of ram.. suspect memory leak.. One solution is turning it off after checked for mail...But i kinda want it minimized so i don't have to check by starting it every now and then..

I am using Thunderbird 115.18.0 and Windows 7 professional (no snarky comments please).

All has been working fine for years, but in the last few days, strange thing have been happening:

In the pane with all of my email accounts, the ">" icon to the left of the first account has been disappearing. This meant I could not look at any folders, including Inbox, Drafts, Sent etc and handmade folders. Cured by closing and opening Thunderbird.

I now have two Archive folders, one called Archive, the other Archives. Both empty, neither can be deleted.

Periodically, when the ">" is present, selecting it (to "V"), the list of folders SLOWLY appears, one folder at a time.

Periodically, the bottom of the Thunderbird window, shows a 'downloading' message, of hundreds of files. Several GB of data has been downloaded over a couple of days.

Opening the Inbox folder, the pane with subject, correspondents, date etc has changed the sort order.

Sometimes, all of the emails in this pane have had their font underlined.

Nothing on my system has intentionally changed,

Any ideas what has gone wrong, and how to put things right would be appreciated.

Thanks,

After an automatic update of my windows 11, the thunderbird has real perfomance problems! the program open very slow, it freeces permanently, that the program is not usable anymore. I have deleted Thunderbird and reinstalled but it still has the bad performance. Thunderbird on my Laptop with windows10 performance without a problem, is fast and does what it was designed for! What can I do??????????????

I have just upgraded to Thunderbird 102.15.1 on my laptop and have a problem with right-click menus on folder names.

The menu appears for a brief instant and then disappears. If I move the mouse cursor slightly then it is redrawn and behaves normally.

Is this a known problem, i.e. requiring a further upgrade?

Thunderbird has become crazy slow. 5-10 minutes to display an email. It's not my email server because my phone connects to and displays email fast. I have been through all the advice that I can find and cleared, checked, disabled everything that might slow it down. Still crazy slow. If I kill it and restart, I get about 3-4 minutes of reasonable performance and then it just stops. Latest Release Version V147.0.1.

i have a fast machine with 32Gb memory only 60% used, everything else runs fast

I don't want to junk Thunderbird, but it's unusable.

Help!

local folders after a certain amount of folders have disappeared. I have made a new folder today, it displayed, closed thunderbird, re-opened thinderbird, and folder disappeared, the .msl file and file are still in the profile/mail/localfolders directory, just not being display under local folders in program, deleted all .msl files, and restarted thunderbird, and it did not recreate the .msl file(s) as well

While checking mail in my inbox, I opened, then deleted a message (message 1). As has been happening lately, there was a significant pause between my hitting delete and the mesage going away. Then I opened another message (message 2), and I found that it had the header for message 2 displayed in the inbox, but showed the text of message 1 when opened. Scrambled messages and headers could be a big problem.

I logged onto the mail server (gmail) directly. It showed me message 2 with the correct header, and message 1 was in trash.

To fix the problem, I deleted message 2 on the server, and waited for it to vanish from the headers in my Thunderbird inbox. Then, I copied it back from trash on the server. After it downloaded to Thunderbird, everything was fine, but I wanted to alert you to the issue. Something evidently can go awry on TB's end to scramble headers and messages, and that is scary.

Running TB 147.0.1 with gmail(imap) as the mail server. I have posted twice in the past week about issues with gmail, and I am suspecting something going on at that end. My TB installation is brand new since then; the problems with logging on and staying connected that I reported only went away when I removed .esr, rebooted, and did a clean install of TB.

Please advise if this is a known problem, and if there are settings I can tweak to prevent recurrence.

Lately, when I try to click on a different mailbox or message , nothing happens. repeating clicks sometimes works, and sometimes i have to first click on what I was previous viewing to get what I want to highlight, or click on different areas of a message or mailbox to get it to work. I am on mac tahoe 26.2. Did not have this problem before. What can I do to fix this problem?

Thanks Dan

A bug perhaps:- If I highlight various messages at once (I use shift and arrow) and then I press delete. When i subsequently navigate to any other message I can't read it, instead I see this message until I quit and reload Thunderbird: We're sorry, but we can't display this conversation, because the messages have been moved or deleted. Has anyone else noticed this and, better still, do you know how to work around it. I'm using Unified Folders by the way, in case that's relevant.

For quite a few months now, Thunderbird has been acting weird. My emails download, I can sometimes open and delete some, but after a short time, it gets stuck on one email and won't open any more at all. I also can't open any menus, but I can change inbox folders, but still only the original email is shown. It's really hard to troubleshoot and try to fix, as I can't get to any of the menus most of the time. This happens in safe mode as well. This is getting really irritating as I've been using Thunderbird for many years, and I'd like to fix it rather than find a new email program.

Hi I was using TB 142 without problems. When upgrading to 143 ou 144.B4 I have problems sending mails to all users after some times. Usually the first mails are sent immediatly but after around 10 mails, I have very slow response (varies from 5 sec to more than 1 minute and sometimes timeout). Usually quitting TB solves the problem but this is very annoying. I went back to 140LTS and sems to have no longer this problem. This was tested on many diffrent networks. I am running under Fedora release 42

Thanks

Actually this is more an observation than a query, but I hope it's helpful. My Thunderbird V147.0 running two accounts on IMAP, Windows 11 and a lot of local folders (35Gb) had slowly got slower, but then just about packed up. e.g. 5 minutes to load one email, 20 minutes to download maybe 25 emails. Then it would stop completely requiring a Task Manager terminate and a restart. I read all the advice and tried a lot of it, but didn't see anything about the "global-messages-db.sqlite" file affecting performance. Anyway I got to having a look at it - 1.37Gb!! Deleted the "global-messages-db.sqlite" file and restarted. Thunderbird was back to normal and now 10 days later the sqlite file seems to be stable at approx 41Mb. I have no idea how it grew so big (33 times bigger than it seems it needs to be), I have never deleted it before and I have probably been using the current Thunderbird configuration for 20 years, but I imagined that reindexing etc would keep it a manageable size, clearly not. I wonder whether there should be a "Clear down Global Messages DB" button.

I recently updated to 147 and my email is not working efficiently. 1) Thunderbird will not open again after closing 2) Email header populates but message will not 3) All emails are in Inbox but none populate email message.

Help!

Thunderbird 140.7.0esr (aarch64) on macOS26.02

For several days now, Thunderbird has been responding extremely slowly to mouse movements or clicks. This leads to undesirable results because emails are suddenly deleted that should not be deleted (due to forced double clicks). Or folders are not opened, or the wrong folders are opened.

The last change was updating Thunderbird. Is this a known bug?

1. I've drafted an email, then hit save / closed the email and opted to "save changes". 2. I try to edit that email, but it is just "flashing" in the preview screen. I right click on it to "edit draft message", but that just brings up a blank email. 3. The status in the bottom left of the screen shows "loading message..." "downloading message", repeatedly. 4. It was working fine earlier in the week, but Thunderbird Desktop Version 140.7.0esr | Released January 13, 2026, seems to be when the problem started?