Event ID 12014 may appear in the Application event log of CAS/HUB Transport/Edge server:
“Microsoft Exchange couldn’t find a certificate that contains the domain name mail.domainname.com
in the personal store on the local computer. Therefore, it is unable to offer the STARTTLS SMTP
verb for any connector with a FQDN parameter of mail.domainname.com.
Verify the connector configuration and the installed certificates to make sure that there is
a certificate with a domain name for every connector FQDN.”
This means that you are missing a cert for a SMTP connector
Here is the solution:
New-ExchangeCertificate -Domain Name “mail.yourdomain.com”, “computername” -Services “SMTP”
Enable-ExchangeCertificate “thumbprint recieved above” -Services “SMTP”
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