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thunderbird 78.3.1 (64-bit) on windows 10 with proton bridge fails sending mail (ssl self signed error)

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  • Last reply by svlad2009

seccentral
seccentral
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The windows version alongside protonmail bridge version 1.3.3 which is latest today 30'th sept 2020 fails to send messages using a proton mailbox . error is Sending of the message failed. The certificate is not trusted because it is self-signed. The configuration related to 127.0.0.1 must be corrected. the configuration was deleted, remade, redone, all per proton instructions and community claims it's a thunderbird bug. the certificate issued by bridge can be seen under Options - Privacy and Security - Certificates - Manage Certificates - Server tab listed as a permanent cert expiring in 2040.

My pc's date and time are correct, i checked so there shouldnt be any time/date issue. I've been using proton and other providers via thunderbird for years, it's my default mail client since 2006. I've had a lot of non-standard mail setups, smime certs, private mail servers with custom ports/auth methods etc. It is not an issue of user error. i tried several times, thought maybe i was just tired initially. It is a bug. or something of the sort. I contacted proton and i decided to post here too. Some reddit threads already a week old exist on this very issue. What is going on and when can a fix be expected ?

The windows version alongside protonmail bridge version 1.3.3 which is latest today 30'th sept 2020 fails to send messages using a proton mailbox . error is ''Sending of the message failed. The certificate is not trusted because it is self-signed. The configuration related to 127.0.0.1 must be corrected.'' the configuration was deleted, remade, redone, all per proton instructions and community claims it's a thunderbird bug. the certificate issued by bridge can be seen under Options - Privacy and Security - Certificates - Manage Certificates - Server tab listed as a permanent cert expiring in 2040. My pc's date and time are correct, i checked so there shouldnt be any time/date issue. I've been using proton and other providers via thunderbird for years, it's my default mail client since 2006. I've had a lot of non-standard mail setups, smime certs, private mail servers with custom ports/auth methods etc. It is not an issue of user error. i tried several times, thought maybe i was just tired initially. It is a bug. or something of the sort. I contacted proton and i decided to post here too. Some reddit threads already a week old exist on this very issue. What is going on and when can a fix be expected ?

All Replies (1)

svlad2009
svlad2009
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I have found another such question here with a such solution - can you try this: The website may try to fallback to TLS 1.0 in a way that is no longer allowed in current releases or may be using a deprecated cipher suite.

You can open the about:config page via the location/address bar and use its search bar to locate this pref:

security.tls.insecure_fallback_hosts

You can double-click the line to modify the pref and add full domain to this pref. If there are already websites (domains) in this list then add a comma and the new domain (no spaces). You should only see domains separated by a comma in the value column.

https://support.mozilla.org/en-US/questions/1055526