The WLC version is 4.0.217 with ACS v 4.0. There are certain clients have intermittent wireless, whereby it connects and disconnects and connects again when using dot1x authentication. But they have no problem connecting to SSID with no dot1x authentication and it is very stable. The DOT1X authentication security parameters is PEAP using MSCHAP, OPEN authentication and WEP encryption, no validate certificate, Win2003 AD. There are about 200 users, it is happening for around 10-15 users. Any suggestions or recommendations.
It is WEP. Anyway, on the client, all the drivers are updated and also patched with Microsoft KB 885453. Could not suspect any major interference in the network as when the client use other SSID without dot1x it works fine.
1. Do you have Microsoft KB917021 or XP SP3 installed?
2. Are you sure that WEP with 802.1x with PEAP is even supported on the WLC? I can't find any docs that list that as a supported option.
3. Try WPA1/TKIP and/or WPA2/AES with 802.1x.
Just because the gui lets you configure something, doesn't mean it works or is supported. For example, WPA1/AES and WPA2/TKIP can be configured but don't work as they are unsupported and invalid. I suspect this is what you are running up against. Nobody else is configuring the WLC the way you are.