Issue Let's encrypt ssl trouble mailserver

[flint]

Server operating system version

Ubuntu 22.04.5

Plesk version and microupdate number

18.0.71

Hi folks,

I'm heaving issues with my mail server ssl cert.

If I do:

user@server:~# openssl x509 -in /etc/postfix/postfix.pem -noout -dates
notBefore=Jul 15 05:45:41 2025 GMT
notAfter=Oct 13 05:45:40 2025 GMT

If I do from external or same server:

user@server:~$ openssl s_client -connect mail.server.tld:465 | openssl x509 -noout -dates
depth=2 C = US, O = Internet Security Research Group, CN = ISRG Root X1
verify return:1
depth=1 C = US, O = Let's Encrypt, CN = R3
verify return:1
depth=0 CN = server.tld
verify error:num=10:certificate has expired
notAfter=Jun 3 20:02:17 2023 GMT
verify return:1
depth=0 CN = server.tld
notAfter=Jun 3 20:02:17 2023 GMT
verify return:1
notBefore=Mar 5 20:02:18 2023 GMT
notAfter=Jun 3 20:02:17 2023 GMT

So, how is the postfix cert linked in plesk?

My setting under Tools & Settings -> SSL/TLS Certificates
Certificate for securing mail Lets Encrypt certificate 20250715 from server pool. [Change]

List of certificates in server pool only one certificate available "Lets Encrypt certificate 20250715"

I renewed today and renamed it, so I don't confuse myself.

Is there anything else I can check?

 

[flint]

Additional Info:

tools & setting -> server server settings -> server name is: mail.server.tld

And I also found another post and did (without success):

plesk bin domain_pref -u server.tld -mail_certificate "Lets Encrypt mail.server.tld"
systemctl reload postfix
systemctl restart postfix