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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

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.

Hi Folks, I use, as do others I know, Thunderbird for Android. Recently it has decided that the SSL Certificate it accepts for fetching emails is not valid for sending and requires you to accept and make an exception for the certificate. Has anyone else found this? I have tested the certificate, provided by Lets Encrypt, on several servers all claiming SMTP, POP3 an IMAP offer valid certificates. Yet Thunderbird still claims it is a security threat. Can omeone off an answer please? I am currently helping others accept the certificate.

Thunderbird ofr Android is V18.0

regards Anthony

I would like to understand how DNS over HTTPS impacts browsing speed and privacy in Firefox.

Details: Hello everyone,

I am currently exploring Firefox privacy and network settings, especially DNS over HTTPS (DoH). I noticed that enabling this feature slightly changes website loading behavior on some networks.

I would like to ask:

Does DNS over HTTPS introduce additional latency? Are there performance differences between providers? Can corporate or public Wi-Fi networks interfere with DoH requests? Is there a recommended configuration for balancing privacy and performance?

I’m interested in both technical explanations and real-world experiences from Firefox users.

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"
     }
   }
 }

}

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.

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

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!

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 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