Thunderbird Community Forum

Why can't I send outgoing email on my BT Premium email account from within Thunderbird, when the Norton VPN. I get a timed out or policy block message. Somewhat perversely, it works when the VPN connection is on. although you warn that VPN connections may be rejected.

Any info or ideas?

Hi there. This morning the Customized Menu Bar in my T-Bird was there, as confirmed by my wife... and then it wasn't. No idea what happened. I spent a long while poking around to try to find what had been inadvertently changed, and came up empty. So, went in to Customize Toolbars and rebuilt the Mail toolbar as I recalled its layout, as we use it a lot every day. Now it seems to be fine. T-Bird is kinda like Windows, where there's more than one way to do something, and sometimes several paths to the same function. I know there are new Keys, or whatever they're called, that replace or replicate the old Customized Menu Bar. But we have been using T-Bird for ages, and though I've noted all the updates and improvements over the years, we are pretty comfortable with the basics that we use, and have not made many changes. So, we're OK. Just thought it was weird what happened. Thanks for being there. Greg Moehl

Config editor has no printer listed. nothing to reset. Printer works with other applications just not TB. Re-installed the printer. Reset the space limiters, which I found were set too low. Restarted TB and computer

Hi,

we use Thunderbird for several business e‑mail accounts (for example info@… and similar), all configured as IMAP, and the same mailboxes are used by multiple people on several computers. Our mail server hostname is nickel.studio4web (Studio4web hosting).

We have noticed the following strange behaviour of messages (usually customer orders):

A new message arrives normally in the “Inbox” folder.

After some time, for example the next day, the same message also appears in the “Trash” folder, but it is still visible in “Inbox” at the same time.

We checked the headers; the Message‑ID field is exactly the same in both Inbox and Trash, so it looks like one and the same mail that exists in two folders at once.

In Thunderbird Server Settings we configured the delete behaviour so that messages are either moved to Trash or removed immediately (we tested both options), and after that we ran Compact on both the Inbox and Trash folders. However, some messages still remain simultaneously in Inbox and Trash.

We know that other team members open the same accounts in other clients / on mobile phones or in webmail, but we are not sure whether that alone can explain this double appearance of the same message (Inbox + Trash).

For example, two order emails from 03.12. were in Inbox only on that day, and today we see them also in Trash, while they are still in Inbox. No one remembers explicitly deleting them.

Questions:

Is this behaviour normal for IMAP in Thunderbird, or does it indicate some bug or wrong configuration?

Is there a way to prevent a single message from being present in both “Inbox” and “Trash” at the same time (so that it is either only in Inbox or only in Trash)?

What else should we check in Thunderbird settings or on the mail server (filters, special IMAP options, automatic cleanup, server‑side rules, etc.) to avoid such “duplicate” messages?

Environment:

Thunderbird version: 140.5.0esr

Operating system: Windows 11 Pro

Mail server / provider: nickel.studio4web (Studio4web hosting)

Thanks in advance for any help and advice.

Good afternoon, I am using Thunderbird for many years now. In the last ~2 years I have seen several times the subfolders of the mail folder disappearing from the list on the left panel. All of them are correctly subscribed. I would like to know if there exists a way to recover them different from deleting the account and recreating it. I am currently running Windows 11 Pro 25 H2 with Thunderbird 145.0.

Did anyone experienced such an issue? Thanks Riccardo

Hello,

I have a MacBook Air M2, and I'm experiencing energy usage issues related to Thunderbird. This has kept happening for a long time now actually, surviving through at least two Mac OS updates, and a huge number of TB updates. Everything's up to date. I tried to follow this: https://support.mozilla.org/en-US/questions/1269944 and this: https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems?_gl=1*86dj4d*_ga*MTkzNzQ0MjA3MS4xNzYyOTY4OTMx*_ga_2VC139B3XV*czE3NjMzMTM3NDckbzIkZzAkdDE3NjMzMTM3NDckajYwJGwwJGgw but didn't succeed. Actually, in my case, the issue is more noticeable: I normally have TB open in background - sometimes everything's fine, and the battery goes down as normal, while sometimes instead the battery drops quickly, and checking in the Mac activity monitor I can see that the CPU usage of TB is totally abnormal. When this happens, I can actually see the activity bar in TB being live (bottom right corner, as it happens when TB is checking for new mails), but never disappearing. When I notice it, I just reboot TB, and the bar shuts off as normal after a quick mail check. Moreover, checking the 24hr energy usage by app, TB is often on top with nonsense values.

I tried multiple times to rebuild the database, and do most of the tricks suggested, but didn't fix. Yes I have a huge mail archive, but the problem is not the standard management of this database: basically it seems that every now and then, TB decides to run some activity which it gets stuck in, and this kills the CPU.

Thank you in advance for your help!

I have two installations of Thunderbird on two different computers 2 different locations, both are new installations. Both are on Windows 11. The one at home, works perfect, the one in my second home too except the unified toolbar is unresponsive, whatever I click there it doesn't respond, The X doesn't close the program, the - doesn't minimize anything, just nothing happens, any advise?

I tried changing the value of the field "Displayed name" (I am translating this from the French, I hope it is correct) and select the default email address of that contact, then clicked "Save". It briefly (for a second or so) displayed the contact correctly (with the new displayed name and selected default email) but then reverted immediately to the previous values. When I clicked to edit it, the changes I had made had disappeared. How do I set the values in a contact??? Thanks.

TB has now locked for me saying "Downloading message 158 of 289 in Inbox..." However, that is just the latest of TB behaving bizarrely over the last few days: filters not working, TB repeatedly re-downloading whole folders and now this is the last straw. Same sort of short pause then total lockup in troubleshoot mode too.

I have to have an Emailer I am not constantly fighting and debugging. My sense now is that the main database structures of my TB have somehow been corrupted.

I think this may go back to [https://support.mozilla.org/en-US/que.../1541906]. That problem transferred to a different folder when I changed my filter to redirect the routine messages to that different filter so it wasn't the folder, I didn't have time to sleuth it further and as it only affected those messages, which were not important, I ignored it and TB worked fine for other things. Then it even stopped happening with new ones of those messages but still if I opened one of the old ones, TB would lock. Again, I didn't really need the old ones so I ignored this.

Disconcertingly, Firefox, my main browser, has today become afflicted with something similar: launches, OK for about a minute, then locks, no different in troubleshoot. I will report that and come back and add the link here but perhaps some mix of Mozilla and KDE and or Ubuntu recent changes are behind this but the TB problem above was there on Ubuntu and has been brewing all week so a shared Firefox/TB issue is not the whole story.

I am not sure how much longer I can persist with TB given the frequency with which I have had really nasty problems with it in recent years. However, I feel a loyalty (I am a financial contributor) and I know that rebuilding my filters in another Emailer will take probably a full day (and I don't know what I'd swap to, using Kmail/Kontact for now so I'm not Emailless). So I would like to have one last go and my wish is to create a clean install and then I hope, rescue my address books and filters from the dying version and see if one last go can resuscitate things. So my questions, as I think the correct answers to this have varied a lot over recent years. I would like answers known to work for TB is 140.5.0esr (64 bit) on Kubuntu 25.10 if possible but Ubuntu 25.10 is obviously close.

• How do I best save and transfer the address books?
• Ditto all my filters (a lot!)

TIA, Chris

I'm new to Thunderbird. Today I installed and exported ALL my data from Outlook for Mac. I then used Olminator to successfully convert to eml and ics files for import to Thunderbird. The eml file import for my email worked great, as did my contacts. However, when I try importing the resulting ics file, I get this error:

If you’re seeing this message after snoozing or dismissing a reminder and this is for a calendar you do not want to add or edit events for, you can mark this calendar as read-only to avoid such experience in future. To do so, get to the calendar properties by right-clicking on this calendar in the list in the calendar or task view.

I've tried importing to the 'Home' calendar, and also creating a new calendar for the import but nothing works.

Any assistance would be greatly appreciated.

Thanks.

Thunderbird version 140.5.0esr 32 bit now seems to dismiss reminders on its own -- i.e. without authorization/permission.

This makes the calendar/reminders feature worthless, at least to me.

Am I missing some setting so the old behavior can return? (Previously, each reminder would have to be dismissed or snoozed manually before it would vanish from the reminders window)

Thank you so much!

Hello there, i use CachyOS and use Thunderbird for my mails, but recently realized that i can login into matrix chat too so i decided to use it because its pretty simple, but when i want to verify my session, i got a problems and even passcode phrase wont help

Here the logs when i start verify device ``` prpl-matrix.matrix: error while handling verification event Buffer.concat is not a function prpl-matrix.matrix: error while handling verification event Buffer.concat is not a function prpl-matrix.matrix: error while handling verification event Buffer.concat is not a function console.error: "Set favicon for page https://addons.thunderbird.net/en-US/thunderbird/search/?q=matrix&appver=145.0&platform=Linux FAILED" [Exception... "Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) [nsIFaviconService.setFaviconForPage]" nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)" location: "JS frame :: resource:///modules/MailUtils.sys.mjs :: setFaviconForPage :: line 1144" data: no] ```

On phone its continiously "loading" secure check but in fact trying 3 times and cancel verification cause of failture, what i should do with it?

Hey Forum, 2 problems.

1. 1. - I have been having some problems w/my paypal account. Someone has been trying to hack into it. Twice in two weeks. I talked to a paypal tech and was told that they are accessing my emails. And she advised changing my email password. I have use Tbird for several years and don't remember having a password. But if I do, where is it, and how do I change it?
2. 2 - For awhile now I have been getting an error message when trying to send an email. (I can recieve, but not send). it says: "Enter your password for ***********@suddenlink.net on smtpsuddenlink.net" Where would I find such a password and where is smtpsuddenlink.net? Also could the above problem be related to this one? They started about the same time.

Using 140.2.1esr (64-bit) on Win, laptop has plenty of disk space free. When writing a long-ish message, I want to stop and think, so I do Ctrl S to Save... Sometimes works fine. Sometimes Thunderbird hangs and does not save, so I lose everything I wrote, very frustrating. Problem happened off and on during many weeks. I cannot replicate the problem on demand. Shut down- restart did not help. Any help will be much appreciated thanks.

In both my Inbox and my saved email folders, when I click on an end-to-end encrypted email, Thunderbird (v145) displays "Loading Message..." and then blocks with a spinning blue "working" cursor for on the order of 30-60 seconds. The Thunderbird dialog then appears to make some progress, as the windows seems to "flash" as if it's being cleared, but the email content doesn't appear. After about another 20-30 seconds, the encrypted email contents appear, correctly decrypted.

This long delay only occurs when I click on encrypted email messages, and it happens every time I click on an encrypted email message, and this behavior only started occurring in the past couple of days (correlated, I believe with Thunderbird updating to v145) so I think it's safe to assume the issue is with end-to-end encryption/decryption in Thunderbird v145.

Up until today I have been able to send emails(with attachments) from my laptop to my cell phone. Now when I want to send an email I receive an error message saying" An error occurred while sending mail. The mail server responded:(VO-1)Message blocked due to spam content in the message. Please check the message and try again. I tried several times since and the same result. Thank you.