If you would like to display a legal message or any other message in a pop-up window when windows starts read below:

1. Start regedit, if you are unfamiliar with regedit please see our FAQ.
2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
3. Modify the key legalnoticecaption with what you want to name the window.
4. Modify the key legalnoticetext with what you want the window to say.
5. Restart.