Warning message is the message that comes exactly before logging into an User account on the Log On screen. This is just for the sake of displaying a message before somebody logs on to the computer.
This can be done in the following way:
Step 2: Navigate to the folder HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\Current Version\Winlogon --- We need to click on Windows Logon folder then we
get list of options to the right.
get list of options to the right.
Step 3: Double click on the option LegalNoticeCaption and change the value put some text in the place of Dialog Caption in the above figure. Step 4: In a similar Way do it for LegalNoticeText edit the text in the place of Dialog Message. This dialog box is presented to the user who tries to log on to the computer after they press CTRL+ALT+DEL 
