Regback.exe is one of the most useful tools in the Microsoft Windows NT Server 4.0 Resource Kit; however, this tool has quirks. The most noticeable regback.exe quirk is how it handles the user profile portion of the Registry (i.e., the HKEY_CURRENT_USER subkey) during a Registry backup. As regback.exe runs, it displays each of the Registry hive files that it's backing up (e.g., SOFTWARE, SYSTEM, SECURITY). In addition, regback.exe consistently displays a message that tells you regback.exe was unable to back up a hive related to the ntuser.dat file, which represents the user profile portion of the Registry, so you must manually back up this file. (Figure A shows this sequence of messages.) If you aren't using roaming profiles, which NT automatically copies to a central location on a network server, backing up the user profile portion of the Registry is necessary to preserve your user profile settings.
Although the recommendation for manually saving the ntuser.dat file, which Figure A shows, looks fairly intimidating, backing up this file is simple. To do so, right-click the control button in the upper left corner of a command prompt window and use the Edit, Mark and Edit, Copy functions from the resulting drop-down menu. Alternatively, you can configure the command prompt window's properties to use the QuickEdit function, which lets you use the mouse to select, copy, and paste text within a text window. Copy the example line that the regback.exe message provides (i.e., regback filename you choose users S-1-5-21-36516332-637091160-1803697834-1001), insert the name of the file you want to assign (e.g., ntuser.dat), then paste this line at the cursor. I hope that Microsoft eventually updates regback.exe to automatically handle this step; in the meantime, you can use this method to back up your user profile.