To simplify end users' Windows NT 4.0 experience, I want to hide the notion of a domain. Therefore, I want to hide the domain drop-down list that appears in the Windows logon dialog box. Windows 2000 supports a registry change that hides this drop-down list. Does a similar change exist for NT 4.0?

No registry change that lets you hide the domain drop-down list is available for NT 4.0. Microsoft lets you hide the domain drop-down list in Win2K to force users to log on to Win2K with a user principal name (UPN), which has the format <username>@<domain name>. Because the UPN always holds a reference to a Windows domain, the domain drop-down list isn't necessary. In Win2K, you can hide the drop-down list by setting the registry value NoDomain UI of type REG_DWORD to 1. This value is in the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon registry subkey.

The driving force behind the display of the domain logon dialog box is the Graphical Identification and Authentication (GINA) DLL. For information about the GINA DLL, see the Microsoft white paper "The Essentials of Replacing the Microsoft Graphical Identification and Authentication Dynamic Link Library," which you can download from http://www.microsoft .com/windows2000/techinfo/adminis tration/security/msgina.asp.

If you need to hide the domain drop-down list in NT 4.0, you can develop a custom GINA DLL. For more information about how to develop a custom GINA DLL, see the GINA white paper. In addition, the Microsoft Windows Platform software development kit (SDK) and the Microsoft Developer Network (MSDN) Library contain useful GINA-related information.