Windows XP A to Z - http://www.softwaretipsandtricks.com/windowsxp
Display message on startup
http://www.softwaretipsandtricks.com/windowsxp/articles/113/1/Display-message-on-startup
Super Admin
 
By Super Admin
Published on 02/23/2005
 
If you would like to display a legal message or any other message in a pop-up window when windows starts

Display message on startup
Start regedit, if you are unfamiliar with regedit please see our FAQ.
Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Modify the key legalnoticecaption with what you want to name the window.
Modify the key legalnoticetext with what you want the window to say.
Restart.