FATAL COMPILATION ERROR : Must be in x.x.x.x format - SOLVED

I’ve used HTML Executable 4.7 then turn to 4.9 version. When I compile my ebook, there is message like this : FATAL COMPILATION ERROR : Invalid Product Version Number specified in “Output/Resources” page. Must be in X.X.X.X format.
What should I do?

  1. You may use number only for the Version Number (for example
  2. If still getting Fatal error, try using same number for Product Number