For SMARTDAC+ GX/GP series, the reference screen (home screen) button that appears in the upper right of the screen when pressing the MENU key is unavailable, and I can’t press it. What should I do?

The reference screen button is unavailable in cases where screens that are supposed to be displayed don’t exist, such as when a display group registered in the reference screen is disabled.

Re-register the reference screen. For instructions, see section 2.2.9, “Registering and Showing the Standard Display" in the user’s manual.