Note: Your machine must be part of a Windows domain for this tweak to work, as the user must be authenticated by the network.
By default Windows 9x doesn't require a valid network username and password combination for a user to bypass the logon and gain access to the local machine. Any user accessing the computer can in fact press ESC or "Cancel" to bypass the logon screen.
This functionality can be changed to require validation by the network before allowing access.
Open your registry and go to the following key:
HKEY_LOCAL_MACHINE\Network\Logon
Create a new DWORD value, or modify the existing value called "MustBeValidated" and set it to equal "1" to require successful authentication.
Restart Windows for the change to take effect.
After rebooting any user that wishes to use that computer will be forced to enter his or her username and password in order to begin using the computer.
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