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Add Security Exception Loop?

  • 2 replies
  • 1 has this problem
  • 4 views
  • Last reply by christ1

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Greetings!

On 2 domains, no matter the account I try to set up, I get an "Add Security Exception" loop when I try to add the account to Thunderbird. All other domains and users on the mail server are configured the same way, DNS records are OK. Username and password are OK. I confirm I can send mail when cancelling the security exception prompt and add the account through advanced config, but I can't connect to read the email without accepting the exception. Any idea why this happens? Using 91.5.0 (64-bit) on Ubuntu 20.04.

Regards!

Greetings! On 2 domains, no matter the account I try to set up, I get an "Add Security Exception" loop when I try to add the account to Thunderbird. All other domains and users on the mail server are configured the same way, DNS records are OK. Username and password are OK. I confirm I can send mail when cancelling the security exception prompt and add the account through advanced config, but I can't connect to read the email without accepting the exception. Any idea why this happens? Using 91.5.0 (64-bit) on Ubuntu 20.04. Regards!

All Replies (2)

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For some reason the screenshot did not upload, so posting here.

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There is a mismatch between the server name you're trying to connect to and the server name in the certificate. This is what Thunderbird is complaining about. Did this start recently? Most likely the email provider installed a new server certificate, but the cert has been issued slightly incorrect. Since you obfuscated the server name this is more or less a guess than a conclusion. You should talk to your email provider.