Remote Desktop connections disconnect

I support a Network running windows 2000 Server Terminal Server and a host of Client OS’s, all of which use Remote Desktop to access the server to run various apps. However they keep getting this error message – “Remote Desktop Disconnected because of a protocol error”
The only thing it says in Microsoft knowledge Base about this in the XP section is if it happens again contact your system administrator. I did find a fix for this but it only relates to Windows CE.
Please Help!!!!