Symptoms
After you set Microsoft Exchange Server 2019 or Exchange Server 2016 to have a static excluded domain controller, the following registry key is created:HKLM\SYSTEM\CurrentControlSet\Services\MSExchange ADAccess\Instance0
After you do this, you encounter a 2080 event approximately every 90 seconds. This registry key is used for StaticConfigDomainController to see what you have set in the value of ConfigDCHostName. However, this key is created regardless of whether you intend to set a value. This issue can occur if you also revert the setting in the StaticConfigDomainController to null as you remove the ConfigDCHostName value but retain the key.
Resolution
To fix this issue, install one of the following updates:
For Exchange Server 2019, install the Cumulative Update 6 for Exchange Server 2019 or a later cumulative update for Exchange Server 2019.For Exchange Server 2016, install the Cumulative Update 17 for Exchange Server 2016 or a later cumulative update for Exchange Server 2016.
References
Learn about the terminology that Microsoft uses to describe software updates.
