What to do if ZKTeco Control Panel shows 'Access Denied (Unknown Format)'?
- JJon TaylorAug 3, 2025
If your ZKTeco Control Panel displays 'Access Denied (Unknown Format)', it could be due to reversed D0 and D1 wiring. Verify that the D0 and D1 wiring is correctly connected. Alternatively, the card type you are using might not be recognized by the system.