Why did TLS stop working after upgrading to Dovecot 2.4?AnswerDovecot 2.4 renamed several SSL settings. If your mail server's TLS stopped working after the upgrade, this is probably why.SourcesDovecot 2.4 SSL Certificate Configuration Change (snippet, the answer above is its summary)https://willem.com/en/2025-06-04_breaking-changes/ (full article)