Thunderbird Community Forum

I have 2 parallel accounts with the same ISP. As of 2 days ago, whenever I try to send mail, I get this message: “Sending of the message failed. An error occurred while sending mail. The mail server responded: Command rejected. Please verify that your email address is correct in your account settings and try again.” I receive mail as normal. Using the other address with exactly the same settings allows me to send normally as I have for the past ten years! Nothing appears different anywhere in the settings. There were no upgrades that I am aware of. I have since found that I can send from my basic little "travel" computer without issue. Any ideas? BTW, using POP mail settings.

When downloading a ICS appointment file to thunderbird calendar it takes you through 3-4 step for one download. Is there a shorter way to download ICS files to thunderbird calendar?'

Continuation of my prior post: https://support.mozilla.org/en-US/questions/1516342

Thunderbird has a routine problem with being unable to log into various mail servers. I have four accounts and they all seem to share this problem.

Most recent update: I've tested this in Windows Safe Mode, and the problem has not appeared. Since I can't do any useful work in Safe Mode, it's hard to give it a thorough test, but so far so good. Also, I have removed AVG antivirus because it was redundant. I have seen no improvement since it was removed.

Can this problem be resolved?

Greetings: Running TBird desktop with email provider Fidei. The email portion works fine (can send & rcv emails)...but upon accessing any of the other features, like Calendars or Lists...the content appears for a moment, then the Login dialog pops & my content for that feature goes blank. I'm providing (what I believe are the correct credentials) but it appears not to accept them...popping again. Are there separate credentials I should be providing for the other features of TBird? It didn't used to behave this way. Thanks in advance for any feedback/guidance. Ed in Tampa

Using FireFox browser

If IMAP folders have been deleted from the server, my understanding of the expected result is that they would no longer be visible on the client. Instead they display in an italic font. Is there a way to make these ghost folders go away? I've tried Unsubscribe from Deleted Folders (Folders display but no tick box to unsubscribe) Deleting cache directories etc all to no avail.

Am I missing something here?

140.7.0esr (64-bit)

I have the thunderbird app on my Linux SSD I set up Thunderbird all went fine when I installed my outlook account, I also have windows 11 so I booted into windows installed Thunderbird there and when I add the same account that i used on the linux. For some reason it wont let me sign in it gives me an account credentails error then send me to microsoft to sign in another way, the recovery email address is not the same as the one I have signed into linux on. I checked the password and recovery email I created and Im able to sign in the password is fine and the recovery email is as well. The thunderbird I installed on windows the account I am trying to add the recovery email is someone elses account not mine for recovery and its saying the password is wrong. I have outlook on my windows desktop and can sign in to that account I even signed out and back in again perfect. I checked the recovery email and password on microsoft web site for outlook and my account credentails are fine. I cant figure this out. It works fine on linux and the shortcut I have on my windows for outlook. But wont allow me to set it up on Thunderbird I installed on my windows. Why is it that thunderbird worked fine setting up on linux with my account but not on windows... I did delete microsoft edge a week or so ago I was wondering if that could be why I dont know.

Can I get an app or add on to my thunderbird email that tells me the email I have sent has been received and opened. An app or add on that does not require the person receiving the email to manually acknowledge the email has been received and read.

In other words when the email is received and opened I get a notification automatically.

PLEASE SOMEONE HELP ME

I'm having problems getting my signature to appear in Thunderbird as it does in my soon-to-be former email client. I've attached pics of the signature as it should appear and as it appears when imported to Thunderbird. I can edit the HTML code, but I'm not sure how to correct things like the image not importing when the link is correct and how to get rid of the dotted line border that shows up in Thunderbird when it does not appear in my current email client signature. I attempted to attach my HTML file, but cannot. I can post the code, if that would be beneficial. HELP!

When I try to send my email I keep getting on screen messages from my old BT account continually asking for new passwords which I keep cancelling but it repeats over and ove again. How can I stop this?

bold text As a message was being sent I tried to save it before the message was completely sent.

When the dust cleared all of my saved messages are gone in all folders and subfolders.

I closed Thuderbird and reopened it. - no saved messages.

I restarted my Macbook Air and opened Thunderbird - no saved messages.

All software was up to date. All other programs seem to be OK.

Now what?

Hello,

As per title, when I step on a new message not belonging to the first thread, the first thread expands automatically. This does not happen when I step on an already read message. I also tried to mark old messages as unread, and the same thing happens. Apparently, it started doing this today, which sounds weird as thunderbird last updated on the 15th, but I didn't notice this type of behaviour before today.

Thunderbird version: Thunderbird Windows MSIX package 1.0 - 140.7.0esr (64 bits)

Vertical view - Cards view

Hello,

I run Thunderbird 146.01 under Windows 11 Version 10.0.22631 Build 22631... TB pulls messages from a POP Server.

Though I have tried many fixes TB keeps reverting to requiring that I manually run both Spam Sorting, and Filter Sorting, usually after running these functions automatically for about a week.

Might someone suggest a fix that will have some lasting benefit?

Many thanks,

Lothar

TB 128 stopped downloading messages from 1blu.de on one 1blu account, another is working.

Switching to pop did not help, neither resetting password on server. Going back to imap did not help. Update to 140.7.1 did not help. In 140, TB connects, searching folders, discovers inbox, but no download of new messages. Inbox is abonniert (subscribed?) and messages are set to loaded to TB.

inbox.msf is updated today, the inbox has a date of Jan 26, latest downloaded email as of Jan. 21, inbox is 3GB and writeable.

In itself, the account at 1blu is ok: the release version (146.0.1) can connect and download messages dated until tonight (=right now).

1blu recommended to delete/reinstall the account but that would mean loosing tags and maybe xnotes.

Any help is appreciated. I write legacy and webextention addons for TB and can run test code in the console or in a temporary addon, if needed/helpful.

Thanks, Klaus/opto

How can I retrieve emails I deleted by selecting wrong parameters in the wrong area. I was in Thunderbird > Acct Settings > Synchronization & Storage and saw "Disk Space" settings. Without thinking I selected --> O ... Delete messages more than [ xxx ] [ ^v ] days old and I changed the number to... [ 90 ] days old. Like an idiot, I for some reason thought I was dealing with messages in "Trash"... go figure. So of course I then noticed in my email Accounts... all messages older than 90 days were removed from all of my folders I had set-up. Many of the folders are now blank, empty of emails that I had moved into the separate folders set-up for different information. I've explored tons of solution responses in "Support" but haven't found a solution to my problem. I really need my older emails back... please help! , Ron.

Hello, My SMTP server uses Let's Encrypt certificate. The website with the same domain has no certificate. Thunderbird refuses to connect to my SMTP server. Test connection to the server (STARTTLS) in account settings sais "The secure connection to the server failed" (or similar. I see bg localization). Another server with Let's Encrypt certificate. Test pases. Clicking View certificate shows webserver cert (from DigiCert Inc).

I can't send emails! :)

Regards! Valentin

I exported my contact list from Outlook to a CSV file. I then cleaned up the file to delete all the columns I am not using and now have only first name, last name, email address. When I import contacts from this CSV file, I only see the first name and email address in the address book. How do I display both first and last names and sort on last names?

This just started 4 or 5 days ago ( 2026.1.23 ish). I did not update TB nor make any changes to the account in question (that I'm aware of). The errors show up every few minutes, with a 'beep' sound and notification pop-up showing up each time - is very annoying.

I was running v145 when it started. I saw there was an update to 147 and installed that; same issue. I restarted TB into Troubleshooting mode and am still getting the error.

This is running on MacOS 15.7.3. Hardware is MacMini (2024) with Apple M4 chip.

Generally I still seem able to received & send emails.

I opened Activity Manager and Error Console. Error console doesn't seem to have much (using 'Multiprocess', with Errors, Warnings, Logs, Debug enabled). Activity manager shows things such as:

<my account name>

   Connection to server outlook.office365.com was interrupted.    09:49
   Failed to connect to server outlook.office365.com.    09:52
   Authentication failure while connecting to server outlook.office365.com.    09:58
   Authentication failure while connecting to server outlook.office365.com.    10:03
   Connection to server outlook.office365.com was interrupted.    10:10
   Connection to server outlook.office365.com was interrupted.    10:14
   Connection to server outlook.office365.com was interrupted.    10:20

There was an error or log entry that I was able to find a few days ago that made me think it was Calendar related, but now I'm not finding that message.