Thunderbird Community Forum

now i am getting mail but my dad and my brother both said they are sending mail and it says undeliverable I tried sending to my self and it came through I have Thunderbird through Comcast. i see mail in Comcast that is coming through so i do not know why. the only thing i could think of was they tried yesterday when the update was going through i received a mail at 7.15 this evening so i have no idea why it would bounce back did nothing to change anything

Hey guys,

So I am trying to create a rule that will delete emails on the server that are 360 days or older.

I know you can go into settings...

>> leave messages on server >>>>>>For at most ,,,,,,,

But from what I have read that only deletes emails on server from when they were downloaded into thunderbird.

I am new to thunderbird so that wont work for me.

So I went into message filter....thinking this would work

>>>>>age in days > is greater than > 360 days >>>>>>>>>>>Delete From Pop Server

But nothing happens???? Help!

Your input is appreciated

In TB 155.01 when I click on Delete the email leaves my Inbox but does not display in the Deleted folder. If I look at Properties in the Deleted folder it shows the correct number of messages in there but the messages themselves do not show in the right hand window. Thus there is no way of seeing what the messages are, just the total quantity in the folder.

Having established a new Outlook account I cannot sign into it properly with Thunderbird - I get authentication failures each time despite all settings apparently being correct, IMAP enabled in the web browser view of the outlook account and so on. Oauth2 set and all server settings good. I have been over and over things. Tried various suggestions of the web to no avail.

I have tried unsuccessfully with three separate machines - two Microsoft 11 laptops and an iMac. All fail.

I can access the account and send/receive emails from a web browser and I have got it working okay with an iPhone, an Android tablet and a Microsoft email client - but not with Thunderbird. I even get a browser popup on the iMac when I open Thunderbird asking if I am trying to sign in - I say yes and it says I am all signed in - but the email doesn't authenticate. I have passcodes all set up etc.

A separate Hotmail account does work with the same Thunderbird client and has the same server settings (apart from the username obviously).

I am at a loss how to resolve this other than move to a different email application.

Any ideas?

I have three email accounts. One is with a btinternet.com domain, and Thunderbird 153.2.0 has started not fetching emails from it while getting all the others. I've removed and reinstalled the account and things work fine for a few days but then it stops again.

All the security settings, etc., seem correct, and I'm not getting any error messages, just nothing happens.

Any thoughts from out there?

How can I change an IMAP server on an existing T-bird account after T-bird deleted the saved password and IMAP server for that account? I tried to change the IMAP server address for an existing T-bird account, but T-bird and/or my ISP deleted the saved password and IMAP server entry for that account, so T-bird cannot get incoming E-mails. I would like to add an/the IMAP server back to the account without deleting the account, adding all of its settings again, and waiting 6 hours for T-bird to re-download all of the most recent 10,000 messages in the Inbox and all of the 15,000 messages in other folders again. The SMTP server and its saved password are still in the Saved Passwords table.

I have Thunderbird 153.2.0esr which runs 2 Email filter (on Inbox and on Outbox)

These filters worked for years.

Suddenly, about at the end of July 2026, the stopped working.

I suspect that one of the latest release of Thunderbird make them stop working.

Is it possible? Any suggest?

Also the filter log registry is empty.

Environment:

• macOS, Apple Silicon (aarch64)
• Thunderbird: 155.0.1 (aarch64), Release channel
• Email hosting provider: Hostinger
• SMTP server: smtp.hostinger.com
• SMTP configuration: Port 465, SSL/TLS, Normal Password authentication

Problem: Incoming email via IMAP works normally, but Thunderbird cannot send any outgoing email.

The error is either:

“The connection to Outgoing server (SMTP) smtp.hostinger.com timed out.”

or:

“Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.hostinger.com failed. The server may be unavailable or is refusing SMTP connections.”

Troubleshooting already performed:

• Webmail can send emails normally.
• Thunderbird can receive emails normally.
• SMTP settings and username have been verified.
• Port 465 with SSL/TLS does not work in Thunderbird.
• Port 587 with STARTTLS was also tested and does not work.
• Tested with a different network/mobile hotspot — same issue.
• Tested Thunderbird Troubleshoot Mode — same issue.
• Updated Thunderbird from 155.0 to 155.0.1 — issue persists.
• Direct TCP connectivity from the same Mac was tested successfully:

nc -vz smtp.hostinger.com 465 → succeeded

nc -vz smtp.hostinger.com 587 → succeeded

Therefore, the SMTP server is reachable from the Mac on both ports, and the same mailbox can send normally through Hostinger Webmail, but Thunderbird fails to establish/use the SMTP connection.

Since sending was working normally before the Thunderbird update and stopped afterwards without any SMTP configuration changes, this appears potentially related to the recent Thunderbird update.

Could you please advise whether there are any known SMTP/TLS/socket issues with Thunderbird 155.x on macOS, or any additional diagnostics/settings I should check?

Whilst exploring settings I managed to create a second duplicate "stgilb@optusnet.com.au" account/profile, ie two inboxes,drafts,sent,spam & trash. In trying to eliminate the duplicate I succeeded in creating a triplicate. How do I return to a single account/profile?

A solution would be greatly appreciated.

After a long explanation, I tried to add a file and lost everything. Starting over! After using TB for over 30 years, I accumulated a large number of personal folders to archive files to. Due to confusion on my part about pass words in Proton Mail and their Bridge, I had to reinstall my ProtonMail account into Thunderbird. Because all my personal folders were connected with the old "account" name, I didn't remove it, and the new addition seemed to be working fine.

After doing some house cleaning to remove duplicate and obsolete files, I wanted to move the folders attached to the old account name, under the new name. I thought I could carefully move my personal folders from the old account, back under the new Protonmail account. Sadly, that doesn't work like that. What I did find was that the original folders which come under the original "account", were created with an older version of TB, which put them in a folder on my HD. But the new default folders ("inbox", "draft", "sent" etc.) are mirrors of the Protonmail Bridge, which is NOT what I want.

So I need someone that knows how to either place the old folders back under the NEW "account", or how to create new folders that ARE on the HD, and then move the files from one place to the other.

Just to help clarify, here's the location of the old folders as per the "properties" info.

mailbox:///E:/thunderbird data/thunderbird/yetudx3p.default/Mail/Local Folders/Friends & family

You can see the address for this folder is on my Drive E: I can go directly to that address on my drive E and see each of the files.

imap://gshantz%40protonmail.com@127.0.0.1/Folders/2009

This folder is from the NEW account of Protonmail - bridge, and is obviously the web address of Protonmail. It is NOT editable, unlike the above location on my HD E:.

Any help or suggestion would be greatly appreciated, gshantz

After swapping to The Bat some years ago I decided to come back to Thunderbird again. So I installed Thunderbird 155.0.1 (64-bit) on my Windows 11 PC, and gradually re-created and connected the the accounts I had on the back. I also installed the ImportExportTools NG addon, then exported my emails from The Bat to Thunderbird. So far so good. However for some reason I created an account twice. There are both for the same GMX account, but one is POP and the other is iMAP. This mistake probably happened after a long session of setting things up and I just forgot about the first account.

I looked through the Thunderbird help and the answer most given was to the Thunderbird menu, select Account Settings, swap to the account you want to delete, and then press the large red DELETE BUTTON on the top level of its settings (next to the DEFAULT button). I've tried this and it doesn't work. There's no confirmation dialog (which is what I was expecting) and if I close and reboot Thunderbird the account is still there.

How can this be fixed?

An example of an added space would be:

director-concertband@oceanside- music.ca

Note that after the second dash in my address above, in the saved HTML Sig Card, the space is added. When I remove the space and re-save the Sig card, the space still returns.

Also note that this happens ONLY in the signature card. The addressing in the email itself is correct. Any help you can offer would be appreciated.

I cannot open the email program with Thunderbird, I have trie to open it by pressing Shift and Thunderbird Icaon, thus the Repair menu opens, I have tried every combination in that , like starting in the secured modus, but it did not help, I have tried to delete the "parent-lock" data in %appadat%\Thunderbird\Profiles\ - it said that I cannot delete it,because it is opened in Thunderbird. Would you kindly help me? Thank you very much

Years ago when I was using Thunderbird there was "fix" for the Advance to next message pop-up, which appears when you press N or P to move to the next/previous message, and that message is on another account. If I remember correctly I think the fix was going into the "debug list" where you could change individual settings if you knew the name of the setting, and set it to off.

Anyway I couldn't find that list at all in the current version (probably a good thing). Is there a setting somewhere or fix where I can turn off this popup?

I try to set up gmail but get the message "Error Creating Account Incoming server already exists."

I have my main Spectrum email set up fine but I have no idea where to even begin with setting up gmail since I get the message above.