Event ID 12016: There is no valid SMTP Transport Layer Security (TLS) certificate for the FQDN of SERVERNAME.DOMAIN.LOCAL. The existing certificate for that FQDN has expired.
The continued use of that FQDN will cause mail flow problems. A new certificate that contains the FQDN of SERVERNAME.DOMAIN.LOCAL should be installed on this server as soon as possible.
You can create a new certificate by using the New-ExchangeCertificate task.
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