Emails from gmail, yahoo have been rejected/not received by our server.

Job ID: 33058587

Budget: $15 – $25 AUD

Emails from gmail, yahoo have been rejected/not received by our server.
This may be due to SSL configuration or mismatch of certificates? I need this to be reviewed and fixed as this issue is also affecting SMTP on other applications to securely send emails from mydomain.com.

How the email is configured:
The domain mydomain.com has been split into two servers, server1 for web hosting & server2 for email.

Both servers are hosted at vultr.com
Server1 is: Ubuntu, using OpenLiteSpeed WordPress.
Server2 is: Plesk used for mail & webmail. SMTP issues - Ports 465(SSL) & 587(TLS) are open but can’t send using secure connection - only port 25 can send but not secure.

DNS is managed at cloudfare.

Error troubleshoot:
SSL certificate installation for ‘mydomain.com’ shows a mismatch of the SSL certificate - see https://www.checktls.com/TestReceiver.
Error => Cannot convert to SSL (reason: SSL connect attempt failed error:14094438:SSL routines:ssl3_read_bytes:tlsv1 alert internal error)
annot proof email address (reason: MAIL FROM rejected).

NOTE: There are multiple applications running for *. mydomain.com that may also require the SSL certificate reinstallation on their respective Plesk environment, This can be manually installed after.
Related categories: PHP Linux Plesk Ubuntu OpenSSL