Lets try to modify windows log on message
Follow Below step:
2) In registry editor, Find the following key:
hklm\software\Microsoft\Windows NT\Current version\Winlogon.
3) Right click LegalNoticeCaption,
click modify,
Type: YOUR MESSAGE HERE,and then click ok!
4) Right click legalNoticeText,
click modify, and then Close your message!
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5) Restart Your Computer.
6) And the message will appear every time you logon!
6) And the message will appear every time you logon!
Reminder : This trick is not recommended for novice pc users.