Cesare,
Do you mean EMAIL clients are getting the warnings? If so, it could be dovecot which supplies the setups for POP3/IMAP… What certs are you using for those? Look in /etc/dovecot/conf.d/10-ssl.conf or /etc/dovecot/dovecot.conf to see if your using the correct certs… Also, you could look at IMAP directly via: openssl s_client -crlf -connect imap.example.com:993 Just replace imap.example.com with your domain or 127.0.0.1 Carl From: Cinghiuz [mailto:[email protected]] Sent: Friday, June 20, 2025 03:25 AM To: [email protected] Subject: [qmailtoaster] Certificate expired Hi there, I've got a strange issue with my production Qmail server: email clients say that the certificate is expired, but if I check on Qmail server I get this result: [root@mail ~]# certbot certificates|grep days Saving debug log to /var/log/letsencrypt/letsencrypt.log Expiry Date: 2025-07-14 19:07:08+00:00 (VALID: 24 days) Expiry Date: 2025-09-12 21:57:08+00:00 (VALID: 84 days) Expiry Date: 2025-07-14 18:56:29+00:00 (VALID: 24 days) Expiry Date: 2025-07-14 18:57:18+00:00 (VALID: 24 days) Expiry Date: 2025-07-14 18:57:28+00:00 (VALID: 24 days) Expiry Date: 2025-07-14 18:57:36+00:00 (VALID: 24 days) Expiry Date: 2025-09-12 21:57:56+00:00 (VALID: 84 days) Expiry Date: 2025-08-16 14:45:25+00:00 (VALID: 57 days) Expiry Date: 2025-07-14 18:58:55+00:00 (VALID: 24 days) Expiry Date: 2025-07-11 16:57:23+00:00 (VALID: 21 days) Expiry Date: 2025-07-14 18:59:10+00:00 (VALID: 24 days) Expiry Date: 2025-08-16 14:45:40+00:00 (VALID: 57 days) Expiry Date: 2025-08-16 14:45:58+00:00 (VALID: 57 days) Expiry Date: 2025-07-14 18:59:29+00:00 (VALID: 24 days) Expiry Date: 2025-08-16 14:46:11+00:00 (VALID: 57 days) Expiry Date: 2025-08-16 14:46:23+00:00 (VALID: 57 days) If I check the validity of /var/qmail/control/servercert.pem I got this result: Common Name : maindomain.it Alternative Names : maindomain.it, otherdomain.com, alternativedomain.it, xyz.com, [...], mail.maindomain.it, mail.otherdomain.com, mail.alternativedomain.it, mail.xyz.com, [...] Valid From : Apr 15,2025 Valid To : Jul 14,2025 Issuer : Let's Encrypt Serial Number : 0x06[...]253 Also if I go to https://mail.maindomain.it I see that the certificate is valid: But email clients (Outlook, Thunderbird, etc.) say that there is something wrong with the certificate: What can I check to fix this issue? Thanks a lot! Cesare
