Virtual DMD window off screen
What it means
The virtual DMD window opens somewhere no monitor can show it — it never becomes visible, without any crash or error.
Why it happens
dmddevice.ini keeps whatever position was last saved and never re-validates it — a stale position from a previous monitor layout, GPU swap, or disconnected screen stays exactly where it was.
How Pincab Toolbox detects it
The virtual DMD's declared rectangle in dmddevice.ini doesn't overlap any currently connected monitor.
Automatic repair
Repair, included in the Pincab Toolbox licence, can fix this one for you. Your files are backed up first, and the fix can be undone.
Check your own pincab
Pincab Toolbox is a free Windows scanner for Visual Pinball X and PinUP Popper. It finds and explains problems like this one. No account, no telemetry.
Download for freeCovered: Visual Pinball X (10.x) and PinUP Popper. Not covered: Future Pinball, Pinball FX, Visual Pinball 9 and the other frontends (PinballX, PinballY).