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Thunderbird, smtp server certificate

laskov548
laskov548
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Hello, My SMTP server uses Let's Encrypt certificate. The website with the same domain has no certificate. Thunderbird refuses to connect to my SMTP server. Test connection to the server (STARTTLS) in account settings sais "The secure connection to the server failed" (or similar. I see bg localization). Another server with Let's Encrypt certificate. Test pases. Clicking View certificate shows webserver cert (from DigiCert Inc).

I can't send emails! :)

Regards! Valentin

Hello, My SMTP server uses Let's Encrypt certificate. The website with the same domain has no certificate. Thunderbird refuses to connect to my SMTP server. Test connection to the server (STARTTLS) in account settings sais "The secure connection to the server failed" (or similar. I see bg localization). Another server with Let's Encrypt certificate. Test pases. Clicking View certificate shows webserver cert (from DigiCert Inc). I can't send emails! :) Regards! Valentin

All Replies (1)

laskov548
laskov548 Question owner
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Additionally, I'm trying to add an exception for an SMTP certificate, but Thunderbird is looking for an HTTPS certificate, and there isn't one.

Why is HTTPS involved here?

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