Use this command
to deselect any portion of the active document that is selected. The Deselect
All command will also remove the column and header lines generated by the user
who has activated the Custom conversion selection for a PDF to Excel conversion.
Shortcuts
Mouse: Left click anywhere on the document area.
Keys: CTRL + SHIFT + A
Example
If this is the currently shown page (everything on it is selected):
After "Deselect All" command is executed, none of the contents of the document
are selected for conversion.