Server 2008 NPS with wireless 802.1x authentication errors

Giganews Newsgroups
Subject: Server 2008 NPS with wireless 802.1x authentication errors
Posted by:  Roostermiester (Roostermiest…
Date: Mon, 2 Jun 2008

I've setup Server 2008 NPS (which is also functioning as a DC) to
authenticate wireless clients through a Cisco 2106 wireless lan controller.
The computer certs are auto installed through Group Policy.  However, when it
attempts to authenticate I recieve the following error:

Log Name:      Security
Source:        Microsoft-Windows-Security-Auditing
Date:          6/2/2008 12:24:38 PM
Event ID:      6273
Task Category: Network Policy Server
Level:        Information
Keywords:      Audit Failure
User:          N/A
Network Policy Server denied access to a user.

Contact the Network Policy Server administrator for more information.

    Security ID:            NULL SID
    Account Name:  
    Account Domain:            COACCESS
    Fully Qualified Account Name:    COACCESS\

Client Machine:
    Security ID:            NULL SID
    Account Name:            -
    Fully Qualified Account Name:    -
    OS-Version:            -
    Called Station Identifier:        00-1F-CA-82-A1-80:coa
    Calling Station Identifier:        00-90-96-A3-E4-1F

    NAS IPv4 Address:
    NAS IPv6 Address:        -
    NAS Identifier:            COAWLC-2106
    NAS Port-Type:            Wireless - IEEE 802.11
    NAS Port:            1

RADIUS Client:
    Client Friendly Name:        COAWLC
    Client IP Address:  

Authentication Details:
    Proxy Policy Name:        Secure Wireless Connections Request
    Network Policy Name:        -
    Authentication Provider:        Windows
    Authentication Server:
    Authentication Type:        EAP
    EAP Type:            -
    Account Session Identifier:        -
    Reason Code:            8
    Reason:                The specified user account does not exist.

I haven't been able to come up with any good reason for the error.  I do
recall having similar issues in a previous deployment and the solution was to
modify the computer name, but that has not worked in this case.  Any ideas
what is causing this error?