Thunderbird Community Forum

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Seem to get this (or similar) error frequently. It's like the things I set randomly revert or change. Have sent images of settings. I certainly don't know what to do.

I use Thunderbird as my email client for my remote machine setup through Parallels Client desktop software for PC. After the recent update, every time I want to send an email, the compose window opens along with another browser window that displays my email account page home screen. Before only the email compose window used to open and after sending the email it would close. Now with the browser window that opens every time, i can't send another email until i close the browser. The attachment that i am including in my email also opens in the same browser window in a new tap and i have to manually close them.

How can i go back to just the email compose window to open and not the browser for every email?

Thanks, Yashar

hi again and thanks for listening when windows updated to 11 they removed Mozilla Thunderbird ESR(x86en-us) publisher Mozilla version 140.5.0 it contained alot of data, address book and many emails. Very disappointing. Is there any thing you could do or is it forever lost thanks again geoff

Hello,

I would like to report a possible issue with the QR code used on the desktop version of Thunderbird to set up or transfer an email account to a mobile phone.

When I scan the QR code from my PC with my phone, the process fails for one specific account. This email address is quite long (36 characters), and I suspect the issue may be related to the address length.

For your information, all my other email accounts (9 in total) were transferred successfully using the QR code, and they all have shorter email addresses.

Could you please confirm whether there is a limitation on email address length for this QR code-based setup? If this is a known issue, is there a workaround or a fix planned?

Thank you for your help.

Best regards, Steve

Thunderbird says this "the certificate for imap.supanet.com does not come from a trusted source". however I have used this email for some time and am happy with it . can I continue with this certificate as I do trust this source

It seems as thought the Thunderbird "Archive" folder is actually reflecting my Gmail "All Mail" folder (which includes mail w/o regard to labels). However, is the Archive folder duplicating these emails on my PC, i.e. is there a copy of each Inbox email, etc? This would double the size it takes up on my PC. Or is it simply acting like the "All Mail" folder online - reflecting all emails.

Hi,

Longtime Thunderbird user. Was online last night, emailing (sending and receiving) perfectly fine. Got online this morning - no changes to my computer or Thunderbird, and suddenly am getting this message:

'Thunderbird could not connect to server inbound.att.net. The connection was refused."

I am able to read mail fine from AT&T Mail via webmail or the Yahoo Mail app. This is strictly an issue with Thunderbird and AT&T.

Any other AT&T users having an issue? Any helpful suggestions? If it matters, I have a bellsouth.net email address.

Thanks!

since last update my *All Mail* folder is empty but at the top it says there are 138,944 messages. I can use some filters and SOME messages appear but by far not all that should match that filter. any clues? thanks,

Thunderbird 140.6.0esr (aarch64) on a Macintosh using Tahoe 26.1

I have 4 emails in Thunderbird 2 are gmail addresses, they work fine. The other two are with my isp (knology/Wowway). The emails are on the Wowway website, but they don't download to Thunderbird. My server name is imap.mail.wowway.com, my port is port 143, connection security is STARTTLS, and normal password.

My last call to my ISP, they said they fixed the problem on their end, now it is Thunderbird's problem. I'm skeptical since they admitted they had a problem and they fixed it, but, can anyone help me? 10 days since it quit working!

On previous PC's I had TB configured to access Usenet This used: Server name: news.eternal-september.org

It would then appear in the list of accounts in the 'Left Hand pane'

I have configured (maybe not correctly) Acess, but nothing appears in teh Left Hand pane.

I attach the create account screen .. and also teh normal TB viw .. and usenet server not shown

As you can see in the screenshot, the umlauts are missing in many emails. Unfortunately, the corresponding fonts can no longer be set in Thunderbird; I use version 140.6.0esr (32-bit). Where can I set that ä, ö, ü, ß (...) are displayed normally? Greetings from Berlin, Markus

Since T146 was auto-installed on 12/12/25 (I think), the Write window in which I compose new messages has ceased to close automatically, although the message is actually sent on time. I use Send Later (with a 5 minute delay). In troubleshoot mode, the window disappears - as it used to. Is there a problem with using Send Later on T146?

Since the last update to version 146.00, under the folder Archives, both the sub folders for 2024 and 2025 have changed to Drafts and I cannot change them back to show the year folder (2024 & 2025). None of my other yearly Archived sub-folders are affected from 2016 - 2023.

Under Properties, both show their respective year correctly - i.e. imap://wbriggs1%40sky.com@imap.mail.yahoo.com/Archive/2024 and; imap://wbriggs1%40sky.com@imap.mail.yahoo.com/Archive/2025

I attach screenshots showing the issue and any help would be appreciated.

I have resisted automatic update of Thunderbird using "check but notify me." For whatever reason on 11/27/2025 Thunderbird was updated to 115.10.1 and it was an unsatisfactory change. Two thing immediately got by attention: 1) the menu bar had been changed and all open tabs had been removed. And 2) I could not find anyway to customize views (see the uploaded image). After two days of fighting this change trying to re-enable custom views, I preserved my mail folders then uninstalled Thunderbird 64-bit and restored Thunderbird 32-bit from an image backup of C:\Program Files (x86)\Mozilla Thunderbird. That of-course required me to set up my profile again and copy the saved mail folders to the new profile directory tree.

I don't like automatic closing of tabs in 115.10.1 and for that alone would not upgrade beyond what I'm now running.

And I can't work without setting up custom views to show messages automatically sent by my UNIX client's nightly backup process. My default view is to "Filter Super User" as all automatic client backup reports come from the root (superuser) account.

The 115.10.1 had some type of filtering named "Quick View" (This is from my memory as I can't consult a running 115.10.1 installation) that is inadequate as it did not offer a way to save the views for later use (that I could find in my frantic state).

You seem to have addressed this topic well but not simple enough for complete non-techies like me who can really only do "Click X, then right hand click Y, then click Z" etc. Is there a noddy solution I could try? Thanks. Derek