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Sending mail with Android Thunderbird results in Certificate Error

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tony202
tony202

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

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

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Platform34
Platform34
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Hi Tony

Thunderbird uses Android's own TLS stack and trust store to validate SSL/TLS certificates. You should check you have appropriate and valid dated root certificates in Android's certificate store for lets encrypt chain of trust validation . I believed the main root certificates are ISRG Root X1 and ISRG Root X2.

What version of Android are you running Thunderbird on?

Laajal dara

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