Here, I've a simple and easy tip for you to change the Logon Message for your Windows:

  • Click Start > click Run > Type Regedit; then click OK.
  • In registry editor, go to hklm > Software > Microsoft > Windows NT > Current version > Winlogon
  • Right click on LegalNoticeCaption > Click on Modify.
  • Type: ME Rocks! or the message you want to display.
  • Click OK
  • Right click legalNoticeText > Click modify.
  • Close your message
Now, each time you start your computer; you will see the message you entered. Have Fun...