Event ID 1142 — DHCP NAP: NPS Availability

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Applies To: Windows Server 2008 R2

Network Policy Server (NPS) is the Microsoft implementation of a Remote Authentication Dial-In User Service (RADIUS) server and proxy in the Windows Server 2008 operating system.

Event Details

Product: Windows Operating System
ID: 1142
Source: Microsoft-Windows-DHCP-Server
Version: 6.1
Symbolic Name: DHCP_IASHELPER_TIME_OUT
Message: The DHCP server is unable to reach the NPS server for determining the client's NAP access state. The error code returned is %0.

Resolve

Install and start the NPS service or repair the network

To establish NPS server connectivity:

  • NPS might not be installed. To resolve this condition, install the NPS component.
  • NPS might not be running. To resolve this condition, run net start nps at a command prompt.
  • The network might be down or misconfigured. To resolve this condition, troubleshoot the network.

To perform these procedures, you must be a member of the Administrators group, or you must have been delegated the appropriate authority.

To install NPS:

  1. At the NPS server, click Start, and then click Control Panel.
  2. Click Programs and Features, and then click Turn Windows Features on or off.
  3. Click Add roles, and then click Next.
  4. Select Network Policy and Access Services, and then click Next.
  5. Click Next, click Network Policy Server, and then click Next.
  6. Click Install, and then click Close.

To perform these procedures, you must be a member of the Administrators group, or you must have been delegated the appropriate authority.

To set the NPS service to start automatically and start the NPS service:

  1. At the NPS server click Start, click Run, type services.msc, and then click OK.
  2. Double-click Network Policy Server.
  3. On the General tab, in the Startup type box, click Automatic, and then click Apply.
  4. Click Start, wait for the progress bar to complete, and then click OK.
  5. On the File menu, click Exit.

To troubleshoot network connectivity:

Communication between the DHCP server and the NPS server depends on a working network connection.

First, use basic network and hardware troubleshooting steps to check that related server hardware (cables and network adapters) is working properly at the client.

If the server hardware appears to be functioning properly, check that the DHCP and NPS servers are available on the network by pinging them individually from another computer on the same network.

If either of the DHCP or NPS servers do not return the ping, there might be a network outage, or the server might be offline or otherwise malfunctioning. If the servers return the ping, network connections are not the problem.

If installing or starting the NPS service or troubleshooting the network connectivity does not resolve the condition, see the NPS documentation.

Note: The ping command uses Internet Control Message Protocol (ICMP) Echo Request and Echo Reply messages. Packet filtering policies on routers, firewalls, or other types of security gateways might prevent the forwarding of this traffic.

Verify

To perform these procedures, you must be a member of the Administrators group, or you must have been delegated the appropriate authority.

To test NPS availability and connectivity:

  1. At the DHCP server, click Start, point to Administrative Tools, and then click DHCP.
  2. In the DHCP snap-in, click Server, click Properties, and then click Network Access Protection.
  3. A green NAP server icon indicates that NPS is available and connected.

DHCP NAP: NPS Availability

DHCP Infrastructure