Ground Controls->Non_PDF->Print->Sequence
These are set up in the Print screen and affect which pages get out printed.
All - Usually you can leave this Ground Control off, as you want all pages to image. If this Ground Control is on, then you will be warned if all pages are set to print, which is not the case for most workflows.
Odd - This Ground Control will trigger if only the odd numbered pages have been set to print.
Even - This Ground Control will trigger if only the even numbered pages have been set to print.