Removing Permissions to an NTFS Partition May Prevent Startup

If Windows NT is located on an NTFS partition and all permissions to the root directory and the subdirectories on that partition for all groups and users are removed, Windows NT will not be able to reboot properly.

The Everyone group includes all users, including the Administrators. In NTFS, because denials are applied before the grants of permissions, if you deny permissions to the Everyone group and it happens to be the only set of permissions, then in essence, no one, not even the System or Administrator, has access to the file.

To work around this problem, do the following:

1. Start the computer from the Windows NT Setup disk 1.
2. Select Repair.
3. Use the Emergency Repair Disk to select the Unsecure System Files option to be able to start Windows NT.
   
   This resets the permissions so that the system can access the files to start.

After you start Windows NT, take ownership of all files and reset the permissions so you can access the files.

Steps to Reproduce Problem

1. In File Manager, choose the root directory, and then select Security, Permissions.
2. By default, the Everyone group has full control to the entire hard drive. Usually, Everyone will be the only entry in the box. Remove Everyone from the list.
3. Choose OK. A warning message appears saying that nobody will be able to access the files. The warning does not tell you that you will not be able to start Windows NT.
   
   Now you won't be able to see any files on the hard drive.
4. Log off and log on again. Windows NT accepts the password, no errors appear, but there will be no Program Manager Shell. Windows NT tries to run the Program Manager shell, but because there are no permissions to run the .EXE file, it does not run.
5. You can log on as anyone, but only a blank screen appears.

If you try to restart Windows NT, the following error message appears: