Check the device first
Make sure the webcam is connected, any physical shutter is open, and the microphone is not muted. Close other ordinary apps using the same devices, such as a video meeting. On a managed computer, ask IT to change settings you cannot access.
Allow access in the operating system
Windows 11: open Settings → Privacy & security → Camera, then Microphone. Allow access for the browser or TrustExam app you are actually using, including desktop-app access where shown.
Windows 10: use Settings → Privacy → Camera and Microphone and check the same permissions.
macOS: open System Settings → Privacy & Security → Camera and Microphone. Enable the browser or app used for the exam.
Allow access for the exam website
In Chrome, use Settings → Privacy and security → Site settings → Camera or Microphone. In Firefox, use Privacy & Security → Permissions. In Safari, use Settings → Websites → Camera or Microphone. Allow the actual exam site and select the intended input device if a choice appears.
Check the preview again
Before the timed attempt, repeat the equipment check after changing permissions. If the camera is still black on Lenovo, check the camera privacy mode in the installed Lenovo utility. If the camera preview loads but connection verification fails, also check the network guide.
Still blocked?
Use the in-platform support chat if available or the support contact in your invitation. Report which check fails, your operating system, browser or app version and the exact error.