After you set Microsoft Exchange Server 2019 or Exchange Server 2016 to have a static excluded domain controller, the following registry key is created:
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.
To fix this issue, install one of the following updates: