Fajar, You answered your own question here "I realized about that WinXP limitation. But the problem occurs when more than 4 clients were currently connected." you cannot do anything to XP to fix this, the only choice is a Windows Server. I do have another question for you though that might help. What applications are needed from windows that cannot be achieved in Linux? You may be able to eliminate the need for windows terminals altogether if you try hard enough. Levi Kemp Technology Specialist Bolivar R-1 Schools 417-328-8943 lnkemp bolivar k12 mo us "The only secure computer is one that's unplugged, locked in a safe, and buried 20 feet under the ground in a secret location... and I'm not even too sure about that one" --Dennis Hughes, FBI -----Original Message----- From: k12osn-bounces redhat com on behalf of Fajar Adianto Sent: Fri 12/7/2007 8:13 AM To: Support list for open source software in schools. Subject: Re: [K12OSN] Windows XP problem Thanks James, I realized about that WinXP limitation. But the problem occurs when more than 4 clients were currently connected. Last time it happened when 9 clients plus 1 on the console. And as I notice, everytime this problem happened, there was a line appended in the wmiprov.log(windows\system32\wbem\logs\wmiprov.log) read "WDM call returned error: 4200". Any suggestion?