ener.hlp (Topic list)
Important Notice
The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.
At least one submenu item must be visible
■ You tried to create a menu where the Visible property of
  all submenu items is set to False. This error also occurs
  when loading an ASCII project where all submenu items
  are invisible.
 
■ Possible solution:
 
  • Set the Visible property of one or more submenu items
    to True.
 
■ If you need additional help, move the cursor to a keyword
  and press F1 to open the Help window.