“We have created the Config.POL file and put it in the NETLOGON share. It has made no difference to our Win XP Pro machines, they just do not see it. It worked fine with Win 98 but does not work any longer since we upgraded to Win XP Pro. Any hints?”

Policy files are not portable between Windows 9x/Me and MS Windows NT4/200x/XP-based platforms. You need to use the NT4 Group Policy Editor to create a file called NTConfig.POL so it is in the correct format for your MS Windows XP Pro clients.