Recently, our chief operating officer (COO) approached me with a unique request: Change the Windows 2000 Professional logon screen to show our company logo rather than the Win2K logo. I wasn't very enthusiastic about the task because I thought it would require more than my basic programming skills. However, after a brief search of the Internet, I discovered that with the right tools the job would be easy.

Related: Customizing the Logon Screen

When you log on, Win2K uses the default Graphical Identification and Authentication (GINA) file msgina.dll. You can change some of the items in this file, including the top portion of the logon screen (i.e., the logo). You can use several utilities to modify the file; I chose Resource Hacker (ResHack.exe), available at http://www.users.on.net/johnson/resourcehacker.

Before you start, double-click the My Computer icon on your desktop. From the File menu, select Tools, Folder Options. Click the View tab. Then, select the Show hidden files and folders option and clear the Hide protected operating system files (Recommended) option. Next, copy your msgina.dll file onto a 3.5" disk. Finally, install Win2K's Recovery Console for fast access to the recovery options in case you have a problem. (To install the Recovery Console, run \install_source\winnt32 /cmdcons.)

To begin the modification process, copy msgina.dll from \Winnt\System32\msgina.dll to \Winnt\System32\msgina2.dll. Create and save the bitmap you want to load. (Win2K Pro's original bitmap attributes are 413 x 79 pixels, so you need to match this size.)

Related: The Dangers of the Windows Welcome Screen

Use ResHack.exe to open msgina2.dll and navigate to bitmap 101, language 1033. (Note that only Win2K Pro systems use this bitmap. For Win2K Server, Win2K Advanced Server, and Windows NT Server , go to bitmaps 101-114, language 1033. Also, each OS uses different bitmaps during different parts of the logon process.)

From the File menu, select Action, Replace bitmap. Make sure that the bitmap you replace corresponds with the entry under Select bitmap to replace, on the right-hand side of the window. Save the msgina2.dll file and apply the change.

A registry setting identifies the name of the GINA; when this registry setting is missing, the OS uses msgina.dll. Use a registry editor (e.g., regedit; Eytcheson Software's Multi-Remote Registry Change—MRRC—3.5, http://www.eytcheson.com) to add the registry subkey HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\Winlogon\Ginadll, and set the value to msgina2.dll. (Note that some third-party programs such as Lotus Notes and Symantec's pcAnywhere also change the GINA file. Make sure to check which version of the file you need.)

To check your new entry, run regedit and go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Ginadll. You must reboot the machine for the change to take effect, although you'll notice the change on the logoff screen. To revert to the Win2K logo, simply delete the registry subkey you created.

Learn more: Changing the Appearance of the NT 4.0 Logon Screen