Thunderbird Community Forum

Thunderbird started crashing randomly about 2 days ago, however, after restart, it would remain running if I switched to troubleshooting mode. I removed an add-on from Bitdefender in troubleshooting mode.

Today I can't even open Thunderbird-- it crashes on launch. It won't launch even if I hit the Shift key or if I turn off antivirus.

Here is the most recent submitted crash report:

Crash ID: ⁨bp-b52cd345-636f-445a-ab4c-764ca0250114⁩

Can someone please give me guidance on what is going on and how to fix it?

Thank you.

I'm able to add an e-mail account but when I go to add a second e-mail account, when it looks up the information, it just hangs with the circle going around.

This is true for two different user accounts on the same computer.

I've uninstalled and reinstalled Thunderbird but it didn't help.

Thunderbird can't be exited without killing from the task manager or shutting down.

When I try to add a new Mail Account, the "Looking up configuration" step hangs indefinitely. I have to force a hard exit to reopen the app. I was able to add my hotmail account without issue, but now that I'm trying to add @yahoo.co.uk , it just freezes up. Thx

Windows 10, newest Thunderbird.

URGENT Version 142 for Windows 64bit is unstable. It freezes over after almost any action with usual Windows "Not Responding" message. Recommendation to Mozilla: Pull back this release and roll back to 141

Dzień dobry, Program po aktualizacji wyświetla tylko stronę "przekaż datek" nie można jej zamknąć. Pobiera normalnie wiadomości, tylko ich nie wyświetla. Proszę o pomoc.

Thunderbird crashed on me last night: "thunderbird killed by SIGSEGV"

The attached image shows that I'm being prompted for an API key. I'm not sure what that is or how to generate one (I presume unique to me?).

I believe I need one in order to file a bug. I can't seem to circumvent it.

Can anyone guide me in the right direction please?

Thunderbird has worked fine for me for years on my Windows 10 Pro machine. The computer works perfectly otherwise--and has a large amount of RAM. But a few weeks ago, Thunderbird started freezing (stops responding) at some point while I'm writing a message.

What happens is that I'll start to write an e-mail message in Thunderbird, and at some random point (from a few seconds to a few minutes) it will stop adding what I'm typing, and soon the text that it was showing grays out. It will then say Thunderbird has stopped responding, and I have no other choice than to close Thunderbird. I have no way of saving or recovering the message I had been typing--very frustrating!

As a partial work-around, I found that if I click on "Save" every time I add a little more to the message I'm trying to write, then at least when I restart Thunderbird I can go to Drafts and recover the message (as it was the last time I clicked "Save").

Thunderbird still works fine for all other functions (reading received messages, etc.). It only has the stopping responding problem randomly when I'm trying to write a message. It can happen while I'm typing--or during a pause between writing sentences. And the timing of the problem is very random and variable (from almost immediate to a few minutes). I tried running Thunderbird in Safe mode, but the problem was the same...

I always keep up with Thunderbird updates. Currently, I'm using version 140.1.1esr.

Can you give me any help with a solution? This problem is maddening!

Thank you,

Vincent Andrunas

Just upgraded to a new system with Windows 11. Avast Security. Installed Thunderbird 128.5.2esr same as on old system. Migrated old emails using MozBackup. Worked great for a day. New emails, archived a bunch of emails to a local folder...

Next day after about 3-5 minutes Thunderbird shows the Hourglass and is not responding. Eventually will go to a greyed out window. I have to kill it with task manager. I noticed that in Activity Manager three calendars were syncing for a long time. Disabled all calendars.

Task manager shows CPU usage but 0 Network and 0 Disk activity. 3 sub processes but only one has CPU. Resource Manager shows CPU and 72 threads. Resource Manager - Analyze Wait Chain - reports "waiting to finish network I/O."

I've tried Troubleshooting Mode. Still froze during Troubleshooting Mode. I've tried moving a large local folder out of the mail folder entirely. I've tried clearing the startup cache. I've tried clearing the system temp folder.

I have a lot of accounts, saved emails and message filters. So I really don't want to start over again with an empty Thunderbird and reset up accounts.

This is an issue that cropped up with the last update to T-bird. It retrieves and displays emails as well as it always has, but now when composing an email reply, T-bird completely locks up, can't shut it down by any means other than using Task Manager and killing the process. Before killing it, though I expanded T-bird's processes, and it listed five instances, one of which read "Not responding." When this happens, the cooling fan in the laptop kicks into high gear, until shortly after I kill T-bird.

Needless to say, this is intensely annoying and inconvenient. I belong to an extremely busy recovery group, and email is my primary contact with them, so this makes things a royal pain. I've had to resort to hitting "Respond" to open a new email, then firing up the text editor to compose the reply, then cut/paste that in and send it. Workable, but really... it *was* working fine, and now it isn't, and I haven't changed a thing, Windows hasn't updated, no new apps or anything... it just stopped working.

I've tried a number of suggested fixes, such as removing all add-ons (removed, not disabled) and themes, creating a new account (which worked okay for about a week, then it too started locking up). About the only thing I haven't tried yet is uninstalling T-bird and re-installing it, which I'll do if I absolutely have to, but I'd rather not go through the hassle of rebuilding everything if there's any other way to fix this.

Is there any kind of information or file/s I can provide that someone may be able to make some sense of? I'd REALLY appreciate it. I've used T-bird since I had internet access (back when Alta Vista was still a thing), and I love it - - no other email app offers the breadth of features that T-bird does, even paid apps. I'd truly HATE to have to switch to something else over this!!

Hello I deleted a lot of emails, and I am not sure if all my old emails have been completely deleted. When I go to open Thunderbird, after about a minute it will freeze up. I have 3 email accounts and I can only view one account but when I try to view another email account, it freezes up, and I have to exit. Before I deleted my emails it all worked great no problems. What did I do wrong and what can I do to get Thunderbird back to working like it use to ? Thanks a lot Sam

Hello,

Starting this week, never happened before....

Using Thunderbird 140.3.0esr (32-bit), Windows 10

If I leave Thunderbird to another application (or even sometimes if I change windows in Thunderbird), when I come back to Thunderbird it is often frozen, in "not responding" status.

I can't see any pattern to when it does this, but it is frequent. The only virus protection I am using is Windows Defender.

I have already tried deleting and rebuilding global-messages-db.sqlite I have compacted folders. I have repaired the inbox folder, which is where I typically am when this occurs.

I'm stumped. Any ideas?

Thank you.

Scott

I've been using Thunderbird for years. I shutdown my computer (MacOS Sequoia) and went away for a few days, and now Thunderbird hangs when I try to use it. I have one main email account which I access with POP, and a couple of other accounts which I access with IMAP. I can access the downloaded messages in the Inbox of the POP account that I downloaded before going away, but I can't read any other folders (I have many folders since I've used Thunderbird for so long), or access the IMAP accounts. Thunderbird shows that I have new mail waiting on the POP server, but it hangs when I try to download them. It does not show mail waiting on the IMAP accounts, although I know new mail is there.

I have tried re-installing Thunderbird, and rebooted the computer, with no change. When Thunderbird hangs, it eats memory until the system runs out, and I have to use Force Quit to terminate it.

It's the first time I've had a problem with it!

Such an annoying problem with current version 128.5.2esr. On one notebook with Windows 11 Hone I install the latest version (no Thunderbird previously installed), works fine.

One another notebook with Windows 11 Home existing Thunderbird freezes. After startup it just hangs, using so much CPU, that the battery is half drained after 30 minutes. Then reinstalling does not help. The same issue persists.

I read that uninstall does not remove the profiles and that cause the issues. Is that possible. Feature request. Also it would be fine to have the option to remove the profile on uninstall, so the non-tech savy user has also a chance of using this client.

The help page doesn't include my version of T'bird, only going up to version 128. When I try to create a new mail account, it only asks for my name and the new email address, then goes into a continuous search loop.

Why for about the last week has Thunderbird been crashing when drafting a message? Often it saves a portion of the in-progress drafting, but not always. What is the fix?

Confused. Version 144.0.1 | Released October 16, 2025 Says 32 bit. I thought I downloaded 64 bit.

Problem: Freezes when I click anywhere on TBird desktop

How do I address the freezing problem?

Thanks Robert

I was able to set up my main account when I installed Thunderbird. The app is fully up-to-date. Now, when I try to add any mail account - enter name and E-mail address - screen goes pale and the doughnut icon spins endlessly. CTRL+ALT+DEL to kill the app. Tried in safe mode - still no go. In every other respect, the app works fine. I can access the other accounts via Outlook, so not a huge deal, but would rather do everything in Thunderbird now that I have switched. Don't want to have to reinstall or create a new profile as I have only just set Thunderbird up (about a month ago).