Event ID 4400 — NPS and Domain Controller Communication

Updated: February 21, 2008

Applies To: Windows Server 2008

Network Policy Server (NPS) contacts domain controllers to perform authentication and authorization for connection requests received from configured RADIUS clients. If NPS cannot contact domain controllers, it cannot perform authentication and authorization, and network access authentication will fail.

Event Details

Product: Windows Operating System
ID: 4400
Source: NPS
Version: 6.0
Message: A LDAP connection with domain controller %1 for domain %2 is established.


This is a normal condition. No further action is required.

NPS and Domain Controller Communication

Network Policy Server Infrastructure