Certain letters are seldom used for Act, Scene, and Page numbering, due to the potential for confusion. Common pairs skipped due to their similarity are:
the letter “I” and the number “1”
the letter “O” and the number “0”
the letters “E” and “F”
Clicking on the Locked Letter Skip List button displays a List of letters of the alphabet. Check those letters you don't want to use.
NOTE: Screenwriter also uses this skip list for use in its numbering of Act Breaks and Scene Labels, if they are set to use Letters.
