Are you using transparent media?

The machine may not be able to read crop marks from transparent media or dark-colored media.

Follow the procedure below to change the crop mark color to white before performing automatic detection again. If the crop marks still cannot be read, change the media you are using.
MEMO

When printing from VersaWorks, select Entire Area under Crop Marks (Print&Cut Alignment) in MarkTab. Crop Mark Color will be printed in black with any other settings.

Procedure
  1. Tap AP-640_Panel_Icon_MENU.
  2. Tap Media Settings - Cutting Settings - Crop Cut Position Adjustment, and then select White for Crop Mark Color.
  3. Print the crop marks again, and check whether the crop marks can be read.