Event ID 2 reason-code 262 I cant authentica wifi users to widnows 2003 radius via Cisco 4400 Controller. Please help

[El CiD]

The same setup has been working for 3 days. All of sudden, the user
cannot authenticate. The user doesnt get prompted to enter
username/domain when connecting to the wifi lan. What follows is the
complete log of the error. There has been no changes to my setup. I
am using a cisco 4400 controller and 1 LWAP access point by cicso.
It connects to my radius server based on windows 2003


Please, any input in the matter is hjghly appreciated. I have been
fighting with this for a few days and cannot get it resolved. Microsft
knowledge base articles have not helped me any.



Server: Windows Server 2003 x64 SP1 or R2
Client: Windows XP Pro SP2
From time to time some of my XP SP2 clients fail to authenticate with
IAS
and thus end up working without WLAN. This is what I get in System
log:

Event Type: Warning
Event Source: IAS
Event Category: None
Event ID: 2
Date: 2007.02.09
Time: 13:49:46
User: N/A
Computer: server
Description:
User host/pc1.firm.com was denied access.
Fully-Qualified-User-Name = firm.com/computers/pc1
NAS-IP-Address = 10.19.247.234
NAS-Identifier = FIRM
Called-Station-Identifier = 00-18-FE-D0-B0-39
Calling-Station-Identifier = 00-90-4B-B9-D3-A8
Client-Friendly-Name = FIRM
Client-IP-Address = 10.19.247.234
NAS-Port-Type = Wireless - IEEE 802.11
NAS-Port = 0
Proxy-Policy-Name = Use Windows authentication for all users
Authentication-Provider = Windows
Authentication-Server = <undetermined>
Policy-Name = WLAN
Authentication-Type = PEAP
EAP-Type = <undetermined>
Reason-Code = 262
Reason = The supplied message is incomplete. The signature was not
verified.

[brentbaxter@gmail.com]

This will fix it.

1. Click Start, and then click Control Panel.
2. Double-click Network Connections.
3. Right-click the connection that you use to connect to the Windows
Server 2003-based computer, and then click Properties.
4. On the Authentication tab, click Properties.
5. Click to clear the Validate server certificate check box.