Each user profile hides a file named NTUSER.DAT. This file contains the settings and preferences for each user. So you should not delete it and possibly not edit it. Windows loads, changes and saves the file automatically for you.
NTUSER.DAT Contains your user profile settings
Each time you change the appearance and behavior of Windows and installed programs, this is the desktop wallpaper. Monitor resolution or even which printer is the standard, Windows must remember your settings the next time you load.
Windows accomplishes this by first storing this information in the registry in the HKEY_CURRENT_USER structure. When you log off or shut down, Windows then stores this information in the NTUSER.DAT file. The next time you log in, Windows will load NTUSER.DAT into memory and all your settings will be reloaded into the registry. This procedure allows you to make personal settings that are specific to your user profile, such as: For the selected desktop background.
The name NTUSER.DAT is a holdover of Windows NT that was first introduced with Windows 3.1
Each user has an NTUSER.DAT file
Windows did not always have full support for user profiles. In earlier versions when Windows was started, each user of the computer saw the same desktop, files, and programs. Windows now better supports multiple users on the same computer. An NTUSER.DAT file is added to each user's profile. You can get there by opening File Explorer and going to either:
C: Users * YourUserName *
or type the following:
in the file explorer's Address bar, and then press Enter.
If you do not see NTUSER.DAT yet, do not worry. Microsoft does not intend to edit or delete this file so it will not be displayed. You can enable the Show Hidden Files option to make the file visible.
You will likely notice that there is one or more ntuser.dat.log files in addition to a NTUSER.DAT file. Each time you make a change, Windows saves your new settings in the NTUSER.DAT file. First, however, it makes a copy and renames it to ntuser.dat.LOG (plus an incremented number) to back up your previous settings. Even Microsoft knows that you should always backup your settings and files.
Do Not Delete the NTUSER.DAT File
You should never delete your NTUSER.DAT file. Because Windows relies on loading your preferences and preferences, removing this profile would damage your user profile. The next time you log in, you will be prompted that Windows can not log in to your account.
Despite the suggestion that you log out, and then correct the problem, the same message reappears. If you try to create a simple NTUSER.DAT file to replace the missing instance, a loop will appear during the initial Setup dialog box, and Windows will never finish logging on.
The NTUSER.DAT file is not a large file by default. It ranges from 3 megabytes on one of our new computers to 17 megabytes on a PC that we have been using for several years. Deleting normally does not recover much disk space. The results, however, can be devastating. If no user profile is required, it is best to remove the user account through Windows.
You probably should not edit it either. Some administrators may do this to make quick changes to many users, but if you're not careful, you can cause problems that are difficult to resolve.
It's best to use regedit to make changes to the registry. If you work in the registry, you should also be careful, but there is a good chance that you will find a guide that will guide you through the steps required. After you edit the registry the next time you log off or shut down the registry, your new settings are saved in the NTUSER.DAT file.