On Jul 22, 2018, at 9:04 AM, Voytek Eymont voytek@sbt.net.au wrote:
I've installed LE certs on my Dovecot a while back, and, it has been working OK since, but, today, an iPhone user said he can't get emails as iphone says 'cert is expired', (if I open mailserver host in browser, padlock shows current/valid cert)
Usually, a browser connects to a web server on port 443, while an email client connects to an IMAP or POP server on a different port, served by different software. Just because your browser receives a current/valid cert, that doesn’t mean your dovecot server is sending the same certificate.
Assuming the sbt.net.au http://sbt.net.au/ in your email address is the address of your dovecot server, I tried
openssl s_client -connect sbt.net.au:143 -starttls imap
And received a cert which includes:
Certificate: Data: Version: 3 (0x2) Serial Number: 03:5b:41:a6:f4:a6:33:eb:5b:ac:af:b8:20:96:f4:0e:20:b9 Signature Algorithm: sha256WithRSAEncryption Issuer: C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3 Validity Not Before: Apr 23 11:11:28 2018 GMT Not After : Jul 22 11:11:28 2018 GMT Subject: CN=geko.sbt.net.au http://geko.sbt.net.au/
Dovecot is sending an expired cert. Pascai is correct; you need to restart it.