EEMS stops responding after TLS endpoint certificate update

Symptoms

After Microsoft update the Transport Layer Security (TLS) endpoint certificate, the Exchange Emergency Mitigation Service (EEMS) stops responding. 

Cause 

This issue occurs because the subject name of the TLS certificate was changed after the certificate was updated. Therefore, the subject name check failed and caused the EEMS to stop working.

Resolution 

To fix this issue, install the following security update:

• Description of the security update for Microsoft Exchange Server 2019, 2016, and 2013: March 14, 2023 (KB5024296)