Symptoms
Assume that you have some Active Directory sites in a Microsoft Exchange Server 2010 environment. You add some Microsoft Exchange servers, in particular, Client Access Servers that have OWA virtual directories configured. In this situation, the following events may be logged: Additionally, event ID 2084 and event ID 1216 may be logged too. These events may cause Exchange to lose its connection with all in-site domain controllers. Then, Exchange may use domain controllers in other sites. In this situation, client users cannot connect to Exchange.
Resolution
To resolve this issue, install the following update rollup:
2936871 Update Rollup 6 for Exchange Server 2010 Service Pack 3
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
Event Information
Event ID 2084 Event ID 2084 that resembles the following is logged when Exchange loses the connection:
Event ID 1216 When the domain controller disconnects the Exchange, event ID 1216 is logged in the Directory Service log:
For more information about Active Directory maximum limits, go to the following Microsoft website:
Active Directory Maximum Limits - ScalabilityFor more information about event ID 2084, go to the following website: