I-Thunderbird Community Forum

Yesterday I upgraded my PC from Windows 10 to 11. Today I discovered my Local Folders are not visible. Searching tells me the messages still exist, but TB does not show the folders. I did the same upgrade a month ago on a laptop (Windows 10 Pro to 11), no problems. I didn't externally back up the messages as I am a dinosaur and don't know how, but at least they are still on the hard drive. Thousands of them though so I need the local folders back. Tried all the fixes I can find on the Community Forum, without success. Can anyone help please? Bob

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

Hi, I have my calendar connected to my Google calendar. It works great in both ways. I can add in Thunderbird and it show up in Google and vice versa. But one issue, when I get a meeting invitation and I accept, it always get in the "Home" calendar and not in my Google one. I have tried to sort them with my Google at top, and if I delete all other calendars it can not be saved at all. And can not find any other settings.

Any suggestions? Or is it just not possible? Maybe a function for a coming update? Or have I just missed out some obvious?

Best regards /Mike

When I try to send an email I get this message

"Sending of the message failed. An error occurred while sending mail. The mail server responded: Authentication required. Please verify that your email address is correct in your account settings and try again."

My email address in my account settings is correct. What can I do?

Issue Related to Backing Up Thunderbird Messages. Trying to back up both my inbox messages and sent messages. Problem relates to backing up inbox messages. First, attempted to back-up (sing the save as function) to desktop (folder). Plan was One Drive would back these up from Desktop. Have 199,000 messages in inbox. Did not save all of them. Then tried to save them in smaller increments to external storage (plenty of storage available). Successful with 4 back-ups of approximated 15,000 messages in each batch. Now will not back-up the full 15,000 ....last successful was 5,000 messages. When it fails, message says "Unable to save the message. Check your file name and try again later." The file naming convention has been the same for all files and have carefully checked to make sure it is not the file naming convention.

What is the problem? Does someone have a solution?

Can you please help me so I can successfully back-up all my inbox messages? Once I figure out an approach want to continue backing up messages using this approach.

Greatly appreciate your help!!

Best, Monica

Why do my new e-mails suddenly go immediately into my "Archive" folder and I have to transfer them to my InBox in the last few days? New e-mails have always gone into my InBox...until the last few days.

I thought for sure that Xfinity was moving messages to junk despite everything. It turns out Thunderbird is doing it. I turned off every setting I could find to keep TB from trying to filter junk. I reset training data. Still perfectly normal messages are sent to junk, and *even marking it as NOT junk, and even the address in the address book* TB moves the message to junk.

Problem in Thunderbird after creating a new email account from Proton Mail - Per9g@pm.me . Not receiving/not retrieving my emails from my email account, but can send emails from it. I have used the code from Proton Mail Bridge in the setup. See technical information below (account9): Programinfo Navn Thunderbird Version 140.3.1esr Build-ID 20250929214837 Distributions-ID Opdateringskanal esr User Agent Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Thunderbird/140.3.1 Styresystem Windows_NT 10.0 19045 Operativsystemets tema Launcher Process Aktiveret Multiproces-vinduer 0/0 Fission-vinduer 0/0 Aktiveret som standard Fjern-processer 1

Virksomhedspolitikker Inaktiv Google Location Service-nøgle Mangler Google Safebrowsing-nøgle Mangler Mozilla Location Service-nøgle Mangler Fejlsikret tilstand false Hukommelsesstørrelse (RAM) 7,9 GB Ledig diskplads 228 GB Konti for mail og nyhedsgrupper ID Navn Indgående server Udgående servere Navn Forbindelsessikkerhed Godkendelsesmetode Identitet Navn Forbindelsessikkerhed Godkendelsesmetode Som standard? account2 Lokale mapper (none) Local Folders 0 passwordCleartext account3 Pggotfredsen@youmail.dk (pop3) pop3.mail.dk:110 alwaysSTARTTLS passwordCleartext Per G Gotfredsen <Pggotfredsen@youmail.dk> asmtp.mail.dk:587 alwaysSTARTTLS passwordCleartext true account4 p.gotfredsen@icloud.com

smtp.mail.me.com:587 alwaysSTARTTLS passwordCleartext true account6 Pergg@live.dk (imap) outlook.office365.com:993 SSL OAuth2 Per G Gotfredsen <Pergg@live.dk> smtp-mail.outlook.com:587 alwaysSTARTTLS OAuth2 true account9 Per9g@pm.me (imap) 127.0.0.1:1143 SSL passwordCleartext Per G Gotfredsen - Per9g <Per9g@pm.me> 127.0.0.1:1025 SSL passwordCleartext true Biblioteker Bibliotek Status Forventet minimumsversion Version i brug Sti RNP (OpenPGP) OK 0.17.1 0.17.1.MZLA.140.3.1esr.botan C:\Program Files\Mozilla Thunderbird\rnp.dll OTR Kunne ikke indlæses. OTR chatkryptering vil ikke virke. - - -

I seem to recall that in the past I was able to change my "From" email address to another one for a 1-time use. Either I forgot how to do that or that option is no longer available. Can you tell me how to do it? I want to use an address that cannot be tracked for some emails (xx@duck.com). Thanks.

I cannot download e-mail from Mozilla Thunderbird. It says "Done" in the lower left corner and will not download when I hit the Get Messages key in the upper right corner. Please help me to be able to download my email.

Lightning Strikes again.

As soon as TB upgraded to 143 I had the following problems:

1. Half my folders disappeared. In this day and age, where emails are "official documents" to prove communications.... 2. I could not delete any email, folder. 3. I could not create a folder.

So, I deleted that installation and reinstalled TB.

Same issues. NO CHANGE with a clean install.

I have two Gmail email addresses. One is used for important messages. As of last Thursday I am not receiving some emails sent to this account. I asked sender to use secondary email and they come through. I’m very concerned that I’m missing important messages and need to get this corrected quickly. Please help if you can. If I need to delete Thunderbird I will but hope not.

In Outlook, it would say that "I replied to this message on xxx" in the header (not sure if that is what it is called, but near the top). I found it helpful to at least see if I have already replied to a message received. Is that feature available in TB?

Hello all!

I use Thunderbird as a local archive for my email. I have two accounts in the application: my home email via my ISP (POP) which I predominately use and my gmail (IMAP) which I don't generally use. There are years of messages in folders and sub-folder under the POP account, but nothing under the IMAP.

I’m up to date with Thunderbird at v140.1.0esr (aarch64) on my iMac with Sequoia 15.8.

On 07/22/2025 I went to download some messages via my ISP POP account and saw that a whole bunch of my email folders no longer had any subfolders and were empty of any messages. Some were also duplicated. Please see the attached image.

I haven’t changed any settings in years, and I do not have any add-ins. One of the nice things about Thunderbird has been its solidity and simplicity.

After every session, I would empty my trash and compact.

Suddenly my email seems to be gone along with sub-folders while top level folders are duplicated.

Wondering if anyone has any suggestions on how to troubleshoot this? Since I don't do anything fancy with the application and with the suddenness of this issue, I can't image I'm the only person having it? I’m quite concerned I may lose many years’ worth of messages.

Thanks much in advance! CPRoot