Creating a form by extension
Note: This procedure applies to forms being
            created in Design Mode in Windows client. For the
            procedure to create a form by extension in the Web Designer, see Creating
               a form by extension (in the Web Designer). 
 
		       To create a new form by extending an existing form in the Windows client:
The Windows client then creates a copy of the base form, gives it the new name, and opens it in Design Mode.