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Sending an email produces the following:

"Send Message Error Sending of the message failed. Unable to communicate securely with peer: requested domain name does not match the server’s certificate. The configuration related to mail.sinnamonlaw.com must be corrected."

After I click OK, the screenshot attached shows up.

Please advise, thank you!

My broadband router set ip address is not secure as it's HTTP What is the solution to able me to access my home router via Wifi in the same location of course which is at home?

I keep getting a certificate error on my Thunderbird. The certificate refers to an email account i no longer have (Personal domain) and i have removed the account in thunderbird, and also removed previous certificate exceptions.

I have been through all menus and settings, and cannot find anywhere where it refers to that domain (and subdomain) I have also removed one entry with that FQDN in the outgoing server section.

What to do?

Hi. I'm using Thunderbird for my POP account and it has stopped sending messages. It just says, Sending of the message failed. Peer's certificate has expired. The configuration related to (my server name) must be corrected. What am I to do?

Hi, With new version 1.143 all accounts are gone, need to re-create my existing mails accoutns (outlook, yahoo, gmail) but all fail on error message "www.mozilla.org uses an invalid security certificate" How to resolve ? Grtz, Jane

When my message filter uses the "Reply with Template" action, the reply e-mail is always PGP encrypted, even when I do not have any public key for the recipient e-mail address. As a result, the reply e-mail is always corrupted.

I am using Thunderbird 140.7.1esr on Windows 10.

I have attached a screenshot of what the reply e-mail always looks like.

In the Template that I am using, the "encrypt" button is not selected, and in the OpenPGP menu of the Template, the "Encrypt" menu item does not have a checkmark next to it.

Does anyone know how I can get Thunderbird to send reply e-mails without using encryption?

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?

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

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?

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

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

Cały czas walczę żeby otworzyć dokument od banku Smime.p7s. Pobrałem ceryifkat .P12 i zainstalowałem na telefonie ale nie wyświetla plików przez wasza pocztę załączników i nie mogę też znaleźć w ustawieniach żeby wgrać ten certyfikat do waszej poczty. Pomocy co zrobić?

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!

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

Dear Mozilla Team,

I kindly ask you to add support for the X25519MLKEM768 hybrid post-quantum key exchange to the domain detectportal.firefox.com (the URL used by Firefox connection testing). This small change would significantly strengthen privacy protection for millions of users who rely on Firefox's connection test URL. As you know, this mechanism has already been successfully implemented on almost all of your other domains. Extending the same protection to detectportal.firefox.com would ensure consistency and close the remaining gap. Thank you very much for your ongoing work on privacy and post-quantum cryptography. I would greatly appreciate your attention to this request. Best regards, Anonymous

Using FF 140.10.1 esr on a windows pc I noticed (probably long after the fact and numerous updates) that there's no longer https:// in the address bar. Having some recent issues with security made me look for this.

When I switched to Edge, the https:// was in the adddresses I was using. There is a lock symbol, but the locks seem to change in their appearance from one browser or website to the next.

Was this verification sign removed and, if so, why?  

Thank you.

Hi, I'm using a policie file to force a family-dns. Ive written the current code down below. Unfortunately this leaves the "manage exeption"-button open, where its possible to simply bypass the block for a specific site. Is there a way to lock this button in the policie file? Thank you very much. {

 "policies": {
   "DNSOverHTTPS": {
     "Enabled": true,
     "Locked": true,
     "ProviderURL": "https://doh16.jusprogdns.com/dns-query"
   },
   "Preferences": {
     "network.trr.mode": {
       "Value": 3,
       "Status": "locked"
     }
   }
 }

}