I-Thunderbird Community Forum

I've used Thunderbird on a pc for decades, love it. Today when I opened it, the 'top level' of folders is entirely missing, it shows only Local folders. I've checked that 'Folder Modes' is set to All Folders, and now I don't know what else to try. Any advice greatly welcomed, I'm struggling to get work done using webmail or phone!

Love Thunderbird - thanks!

Can't seem to find what folder an email is in doing a search. The list of results doesn't show it and can't see it in the email. Maybe missing something. I sort emails by folders so not knowing the folder makes it hard to find what folder it is in (such as I may want to move that email).

Jim

Hello! I'm having a problem where a specific tag keeps un-applying itself. I have a number of filters that look for specific words in emails, and tag them accordingly -- all of my other filters are working just fine, but one specific one has decided to stop working. It has exactly the same settings as the other ones, and when I manually run the filter, it correctly applies the right tag.

But, minutes later, the tag will un-apply itself, and I cannot figure out why. For some reason, an older message is staying correctly tagged with that filter, but newer ones un-apply the tag. This same filter and tag used to work just fine. Other tags on emails from the same source work fine, too.

Auf der Öffnungsseite erscheint normalerweise links ein schmaler Streifen mit den ganzen Ordnern, wie Posteingang, gesendet usw. mit der jeweiligen Anzahl der E-Mails. Im übrigen Feld rechts daneben sind alle E-Mails einzeln aufgeführt. Jetzt erscheint manchmal auf der Öffnungsseite eine andere Ansicht, ähnlich wie die Konteneinstellungen. Mit mehreren Versuchen kreuz und quer gelingt es dann wieder die normale Ansicht zu erhalten. Vermutlich habe ich mal irgendeine falsche Taste gedrückt, so daß sich die Ansicht plötzlich geändert hat. Könnte sich das Problem lösen, wenn ich Thunderbird neu installiere oder gibt es eine einfachere Lösung?

I use Thunderbird 159.0 (64-Bit), german version, on Windows 11. I have integrated as well 2 local calendars as well as 3 calendars maintained on my synology disk station. Today I have noticed that Thunderbird Calendar does not work anymore: I do not see my calendars (the calendar sheet is empty) and the tool does not react neither on the calendar options (the three dots ...) nor on add calendar ("Kalender hinzufügen"). Is it possible to reset or de-installate the calendar tool? Or to delete an re-add the calendars?

(The calendars on my disk stations work fine on the disk station and are still accessible with Android Business Calender.)

Hello My previous computer has crashed. C:/ is not available any more. In my previous computer, I had two hard drives: a C:/-drive (an SSD) where Windows and other software were installed, The second hard drive was a conventional drive (D:/) where I stored all my files, documents, images, and so on. On this d:/ I also had several programs installed including Thunderbird. On that previous computer, I saved and organized my emails into subfolders within Thunderbird.

Is it possible to recover my address book in Thunderbird? Is it possible to find/recover my saved emails? Could they perhaps be saved somewhere on my previous C: or D: drives?

I have an old copy of my C: and D: from 2025 I have also a complete copy of my D: from my old computer.

I have now bought a new computer and installed Thunderbird. I would be very grateful if this could be resolved. Kind regards Anders Quant

My Thunderbird installation (159.0/Windows11) has evidently just updated, and my Calendar tab is suddenly a complete blank space. There's a support article here that appears to discuss exactly this situation, and gives precise steps for getting into "Config Editor" in Advanced Settings, entering a long search string, and issuing a Reset command. (Mail and contacts are just fine.)

Which I tried...

But there is no "Config Editor" button in the dialog I get when clicking Advanced Settings at the bottom of the Settings tab, only a mostly blank screen with no list of settings and a dialog box in which one can enter text (with options for "Boolean", "Number" and "String"). And entering the search string given in the support article produces, with a bit of finagling, a toggle that will change its setting from True to False and back again (and a trash-bin icon that offers to delete it), but neither "True" nor "False" produces any instance of a "Lightning" extension in my list of extensions (which is short and uncomplicated), so (a) I can't delete the extension as instructed, because it's not there, and (b) restarting Thunderbird only continues to give me the unhelpfully blank Calendar tab. (And I do mean "blank" here - there isn't even an empty calendar grid on that tab at this point.)

I *think* the article is probably right that my data is still there (I can see .ics files with current dates in File Explorer), but at this point I can't get at it and can't seem to get the interface unstuck.

Is there a way to pin an email to the top like Outlook? also, I would love to be able to create a unique signature like Outlook. Is that possible too? I tried to just copy and paste and it came out much like this. Crappy.

Thanks!

This has happened twice now when I open Thunderbird. My first email account on the left pane comes up with just the name of the account, no inbox, no folders, no nothing underneath it and it does not expand to show them. I'm not sure why this is happening, but the first time I actually had to completely delete and readd that account to fix the problem. I've searched various places for answers -- change folder views, change layouts, various other suggestions -- but nothing works to resolve the issue. Any help would be greatly appreciated as this is really annoying.

• • Subject: Severe recurring UI freezes after upgrading Thunderbird from v114 to v150+ — application becomes unresponsive after being left idle**

Hello Thunderbird Support Team,

I'm experiencing a serious and persistent performance issue with Thunderbird that began immediately after upgrading from version 114 to version 150 in September 2026. The problem has continued through multiple subsequent updates and is now severely affecting my daily work.

I've been using Thunderbird for years, and it worked reliably before this major upgrade.

• • The problem**

Thunderbird launches normally and initially works perfectly. However, after I leave it open in the background while working in other applications, it frequently becomes completely unresponsive when I return to it.

Specifically: - Thunderbird is initially fast and responsive after launching. - After approximately 5–10 minutes, or sometimes after a longer period of inactivity, it begins experiencing severe lag or freezes completely. - When I switch back to Thunderbird, the interface is often unresponsive for several minutes. - I often have to force-close the application through Windows because it becomes practically unusable. - Restarting Thunderbird temporarily restores normal performance, but the problem eventually returns, when it's left idle. - The issue occurs repeatedly throughout the day and makes it very difficult to use Thunderbird reliably.

Importantly, this is not simply slow startup performance. Thunderbird initially works perfectly, and the freezing develops after it has been running for a while, particularly when left in the background.

• • Version and environment**

- Operating system: Windows 11 Pro, 64-bit - Thunderbird version before the upgrade: 114 - Version initially upgraded to: 150 - Subsequently confirmed version: 156.0.1 (64-bit), on September 29, 2026 - Problem first appeared: September 2026 - Problem still present: October 22, 2026 - Current Thunderbird version: 158.0.1

• • Troubleshooting already performed**

1. **Global search indexing:** I noticed that Thunderbird's Activity Manager frequently displayed "Indexing messages." I suspected that indexing might be causing the problem.

2. **Disabled Global Search and Indexer (Gloda):** Unfortunately, this made no meaningful difference. Thunderbird continued freezing even with global indexing disabled.

3. **Multiple Thunderbird updates:** The application has been updated repeatedly since the initial upgrade, but the freezing has persisted.

4. **Restarting Thunderbird:** Temporarily resolves the problem, but only until Thunderbird has been running for some time.

• • Additional unusual behavior: Google OAuth authentication**

On at least two occasions, after force-closing an unresponsive Thunderbird process, Google Chrome unexpectedly opened a Google authorization page saying:

"Mozilla Thunderbird Email wants access to your Google Account."

The page also indicated that Thunderbird already had some access to the Google account.

After clicking "Continue," Chrome redirected to a localhost address (127.0.0.1 equivalent, using a dynamically assigned port), which failed with:

"ERR_CONNECTION_REFUSED — localhost refused to connect."

I suspect this happens because Thunderbird is no longer running to receive the OAuth authorization callback.

I'm not sure whether the Google authorization issue is directly related to the freezes, but the repeated timing is suspicious and could indicate a background synchronization or authentication problem.

• • Impact**

I use Thunderbird extensively for professional correspondence and managing my translation business. These recurring freezes are seriously disrupting my workflow.

The problem has now persisted for over a month, despite updates and troubleshooting. It is becoming increasingly difficult to continue using Thunderbird in this condition.

• • What I would appreciate help investigating**

Could you please advise on how to identify the background process or operation that causes Thunderbird to become unresponsive after it has been running for several minutes?

In particular, I would appreciate guidance on:

- Whether this is a known regression affecting users who upgraded from much older Thunderbird versions. - Whether IMAP synchronization, background authentication, or Google OAuth activity could be responsible. - Whether there are diagnostic logs or performance profiles I can collect while Thunderbird is frozen. - Whether a particular database, profile component, or setting could be responsible without requiring me to rebuild my entire Thunderbird setup. - Whether there are known fixes or workarounds.

I'm happy to provide additional diagnostic information, screenshots, or logs if that would help identify the cause.

I would particularly appreciate a way to capture what Thunderbird is actually doing during these freezes, rather than continuing to try speculative troubleshooting steps.

Thank you in advance for your assistance!

Functioning normally until it wasn't 5 days ago. Can reach outgoing servers but nothing goes beyond. Initially received emails but at this point neither receiving nor sending. No changes on my end. It just started happening.

I'm having problems with my default email account in thunderbird which might have started with the 28/10 update. Most times when I open TB the default account has no folders (inbox, spam, etc). To get them to appear I have to restart it. At other times it has all the folders present and all expanded including archives. When I can access my inbox the sort order is always by date descending so the oldest email is at the top which I don't want. If I click it to set it to ascending order it sets back to descending the next time I open TB. I've tried repairing the inbox but it makes no difference.

Wenn ich im Terminkalender einen Termin neu eintrage oder bearbeite erschnt ein Bearbeitungsfenster. Darin sind alle Eintragungen weiß auf schwarzem Hintergrund (OK).

Nur im Teilbereich "Beschreibung" erscheint seit einigen Wochen der Text schwarz auf schwarzem Hintergrund und ist daher nicht lesbar. Erst wenn dieser Text markiert wird, erscheint er gut lesbar weiß auf blauem Hintergrund.

Wie kann ich die Schriftfarbe hier wieder zu weiß auf schwarzem Hintergrund ändern?

Since yesterday , Thursday 29th October. Thunderbird has only been displaying the "Inbox" for my account, no emails are visible in it and all of the directories including the deleted emails directory and spam directory are absent. I have Windows 11 installed. I am using the IMAP server for incoming email and have checked that all the settings are correct. My account displays no incoming emails but can send emails. The directories are still absent when running Trouble shooter and the inbox is still empty. In the Account Settings - Server Settings I tested connection to the server and it said secure connection made - this worked for both outgoing and incoming servers. I have tried uninstalling and reinstalling Thunderbird but the issue persists. Although I do not change any settings the full set of directories will occasionally appear along with some emails and then seconds later disappear again. My email account is working fine on my phone and tablet using gmail.

I have used Thunderbird for years but now I am getting frustrated. I have 2 spam folders that randomly put valid emails into them and I have normal folks sending me emails that either go to spam or directly to trash. How do I totally reset this program to start over again for normal use? Thanks, Vern

My profile contains 30 years of work emails which I sort as received into organized folders, stored on my computer. This archive is used frequently to search re projects, correspondence.

My email provider is shutting down. I have already set up my own POP3 server, with new email address.

I'm using webmail until I'm confident I can make the transition w/o screwing up! [Had one storage melt-down which required weeks of work to recover folders from a backup. Once burned, twice shy.]

>> How do I set up/alter Thunderbird profile and/or folders so that emails coming in to NEW address go into the existing inbox/profile folder(s)?

I want to be able to search both NEW and archival emails w/o having to switch between folders/accounts/profiles.

Bonus Q: The old provider is shutting down 12/15/26. While my correspondents adjust to my new email address, being able to see/process emails sent to the old address w/o changing profiles, etc., would be great.

Thanks!!

Thunderbird does not download SPAM until I open the spam folder

This is an existing TB account installed on a new pc, and somehow I failed to copy the spam list across. So for the next few weeks it has to learn all over again. And at the moment there are a lot of false positives.

So when I click on the spam folder it takes some time for all the messages to download. I'd like them to download automatically, so when I click on the spam folder the messages are all there waiting for me

Yes it's IMAP