Start with the right checks.
A camera problem may be physical, an application choice or a permission setting. Start with the visible controls and test whether the issue happens outside the meeting application.
What to do next.
Check for a physical camera shutter or privacy switch on the laptop or webcam.
Open the Windows Camera app and see whether it shows a preview.
In the meeting application, select the intended camera. Close another application that may already be using it.
Review camera permission settings under Privacy & security. Allow the trusted application you intend to use, following any business policy.
Check the result.
Return to the application’s preview and confirm that the correct camera works. Test after a normal restart if the problem was temporary.
Stop and get help if…
Windows does not detect the camera, the picture repeatedly fails or permissions are managed by your organization. Ask for help before installing a driver from a search advertisement.