Thunderbird Community Forum

In Plain English how to use and secure encryption on all outgoing emails please and whether or not to use this great advantage. Many thanks to all those who contribute to this work, PB

https not recognized by Firefox in 151 Thunderbird on silicon iMac with Sonoma. Tried & checked many solutions with no results.

Firefox browser primary , always Nothing in Modified Important Preferences With Extensions off still a problem

Mozilla suddenly says "The certificate for mobile.charter.net does not come from a trusted source." It will not let me get my emails. Is this a problem with Thunderbird or Charter (Spectrum) I am able to receive email on my I Phone. I do not know which Thunderbird version and can't find it using your instructions. Help please

When i try to update my schooles secure mail, i get the nev certifikat and the Root, and Ca1 under autoreties and give it the right rights but it keeps giving me this error message " Certificate verification failed with the following error: The peer's certificate issuer is unknown. (Error code: SEC_ERROR_UNKNOWN_ISSUER)"

I am using Thunderbird 151.0.1 (64-bit), and I get the "trusted source" message in a pop-up every time Thunderbird checks for email. There is only an option to Dismiss presented. My account name changes color to red and has a red triangle with an exclamation mark displayed. I went to Settings > Privacy & Security > Security > Certificates > Manage Certificates and looked at all the certificates listed in the Certificate Manager > Authorities (which is the only section with anything listed) and don't see anything from mobile.charter.net. I can go to SPECTRUM.NET (Charter) and view my email with no problems. I'm at a loss as to be able to view my email in Thunderbird.

Receiving emails was no problem, but when sending one I was repeatedly asked for my password. I did check the save password in the dialog box. I checked the account settings and saw a yellow alert next to certificate exception and clicked on remove. That apparently was a mistake because now I can't get into email since the security certificate is not valid. Reinstalling Thunderbird may be needed, but I need some advice before I try anything else.

I've been trying to set up a GPG key, but Thunderbird doesn't recognize my pub.asc file. So I created a PGP key thru Thunderbird and I would like to export it as ASCII-armored public key.

Dzień dobry, podczas tworzenia wiadomości i próbie zapisania jej na później, otrzymuję komunikat:

Ostrzeżenie Błąd podczas zapisywania szkicu - W Twojej bazie kluczy nie można odnaleźć identyfikatora klucza „0xD3ADE4868E262032”.

Nie potrafię tego naprawić. System iOS na Mac.

Proszę o wsparcie.

Pozdrawiam

I received 2 notifications stating that 1) The certificate for imap.gmail.com does not come from a Trusted Source and 2) You are about to override how Thunderbird Identifies this site. Legitimate banks, stores and other public sites will not ask you to do this. This site attempts to identify itself with invalid information. The certificate is not trusted because it hasn't been verified as issued by a trusted authority using a secure Signature. I have been with Thunderbird for around 20 years and have contributed to it twice, so please help me!

I have problems every time I try to fetch my imap gmail, with Thunderbird complaining that: "The certificate for imap.gmail.com:993 does not come from a trusted source".

As near as I can tell, imap.gmail.com:993 is still the recommended setting for

Version is Thunderbird 148.0.1 (64-bit). Adding an exception for the missing certificate does not seem to make a bit of difference.

I do not know if the use of Bitdefender as my security and vpn software is a factor. I notice that the certificate (exception certificate?) shown when I click on View Certificate in my gmail account settings appears to mention Bitdefender, so perhaps that's a factor. That certificate looks as follows:

Certificate Subject Name Common Name imap.gmail.com Issuer Name Country US Organizational Unit IDS Organization Bitdefender Common Name Untrusted Bitdefender CA Validity Not Before Mon, 02 Feb 2026 08:37:57 GMT Not After Mon, 27 Apr 2026 08:37:56 GMT Subject Alt Names DNS Name imap.gmail.com Public Key Info Algorithm Elliptic Curve Key Size 256 Public Value 04:2D:20:DA:19:33:1D:AC:28:91:52:02:EB:B8:7E:33:C0:B7:E4:F3:5E:4E:88:92:E5:7E:BB:30:0C:6C:E4:84:A8:3D:D7:49:9B:22:C8:C0:BB:01:80:4B:84:30:3A:3B:73:70:8F:AB:EB:C0:F0:D5:7B:8B:0B:64:1B:DC:76:67:41 Miscellaneous Serial Number 1A:50:ED:15:50:A1:A7:93:5D:05:8A:CD:85:A5:15:FD Signature Algorithm ECDSA with SHA-256 Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 12:8A:58:44:DF:B5:E1:E4:EF:CC:F7:35:09:BA:6E:88:86:16:15:78:F9:28:52:23:FC:0E:E9:69:D1:AF:21:86 SHA-1 A3:30:CB:65:39:51:46:9B:3B:BC:0B:B9:09:DD:26:40:A8:52:25:3D

certificate for imap <edited>@peternedsmith.co.uk is not valid, someone could be trying to impersonate the server and you should not continue, on clicking the more info, on the panel that comes up, if I click on get certificate, the selections below get greyed out and nothing happens, I have viewed the certificate, and it appears to be from the US, I have taken a screenshot of the top part of it, which is below. Regards Peter Smith

DEUTSCH (English see below(:

Hallo zudammen,

Konfiguration: - Window11 25H2 (aktuell) - Thunderbird Beta-6 (BuildID=20260213180051) - gpg2.5.17 (Gpg4Win 5.0.1); siehe auch: <https://www.gpg4win.de/>

Der bisherige und standarmärige Installationspfad von "Gpg4Win": "C:\Progam Diles (x86)\Gpg4Win\" wurde softwareseitig auf: "C:\Progam Diles\Gpg4Win\" geändert!

Bug 1967121 (Closed) => thunderbird148 --- fixed! <https://bugzilla.mozilla.org/show_bug.cgi?id=1967121>

Zur Zeit verfolge ich die Änderungen bezüglich der externen Schlüsselverwaltung in Thunderbird-Beta, da das Arbeiten mit externen Schlüsseln in der esr- und in der relesease-Version von Thunderbird seit der offiziellen Herausgabe von gpg2.5.x absolut nicht mehr möglich ist! Die geheimen Schlüssel für das Entschlüsseln und Signieren werden mit gpg2.5.x nicht mehr gefunden!

In der Schlüsselverwaltung von TB-Beta befinden sich meine öffentlichen Schlüssel und alle öffentlichen Schlüssel meiner Kommunikationspartner. Extern sind meine geheimen Schlüssel gelagert. Folgende Präferenz wurde aufgrund von gpg2.5.x hinzugefügt:

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2026-02-26-10-04-58-df59be.png

Allerdings erscheint nach all diesen Maßnahmen die Fehlermeldung: "The secret key that's required to decrypt this message is not availlable."

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2026-02-26-10-05-45-d8280e.png

Mit Herausgabe von Thunderbird/148.0 (release) sind dort die gleichen Probleme mit der externen Schlüsselverwaltung zu bepbachten!

Mit Versionen gpg < 2.5 funktioniert unter Windows alles problemlos!

UNTER LINUX haben hier Änderungen an der Präferenz: "mail.openpgp.load_untested_gpgme_version" nachweislich keinerlei Auswirkungen!

Was übersehe ich?

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ENGLISH:

Hello,

Configuration: - Window11 25H2 (current status) - Thunderbird Beta-6 (BuildID=20260213180051) - gpg2.5.17 (Gpg4Win 5.0.1); see also: <https://www.gpg4win.de/>

The previous and default installation path of "Gpg4Win": "C:\Program Files (x86)\Gpg4Win\" has been changed by the software to: "C:\Program Files\Gpg4Win\"!

Bug 1967121 (Closed) => thunderbird148 --- fixed! <https://bugzilla.mozilla.org/show_bug.cgi?id=1967121>

At the moment, I’m following the changes regarding external key management in Thunderbird Beta, because working with external keys in the ESR and release versions of Thunderbird has become absolutely impossible since the official release of gpg 2.5.x! The secret keys required for decryption and signing are no longer found when using gpg 2.5.x!

In Thunderbird Beta’s key manager, my public keys and all public keys of my communication partners are present. My secret keys are stored externally. The following preference was added because of gpg 2.5.x:

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2026-02-26-10-04-58-df59be.png

However, even after all these measures, the following error message appears: **"The secret key that's required to decrypt this message is not available."**

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2026-02-26-10-05-45-d8280e.png

With the release of Thunderbird 148.0 (release), the same problems with external key management can be observed there as well!

With gpg versions **older than 2.5**, everything works flawlessly under Windows!

• • UNDER LINUX**, changes to the preference

"mail.openpgp.load_untested_gpgme_version" have demonstrably no effect at all!

What am I missing?