A computer feature or peripheral that has completely stopped should be separated into driver, permission and physical-connection layers before assuming component failure. For Windows webcam, first open Camera, check the privacy shutter/indicator and compare another app.
What this covers
- Windows webcam with this exact failure state
- Diagnosis across hardware privacy shutter versus OS permission, app selection and USB path
What it does not cover
Try in this order
0 of 4 completedCapture the exact failure state
ReversibleCheck Device Manager or System Information for whether the hardware is even detected, and whether an error code is shown. Expected behavior: expose video to authorized apps at a supported resolution.
Isolate the component boundary
ReversibleOpen Camera, check the privacy shutter/indicator and compare another app. Test the peripheral on a different port or user account, and test a different peripheral on the same port. Boundary to separate: hardware privacy shutter versus OS permission, app selection and USB path.
Correct only the proven cause
ReversibleGrant the correct permission, select the camera or replace the failed cable/device. Reinstall or roll back the driver, or grant the missing app permission.
Verify and stop safely
ReversibleConfirm the feature works after a full restart in at least two different applications. Disconnect for heat, liquid, damaged USB or an indicator that behaves unexpectedly.
Evidence ledger
Sources behind this answer
Exact questions