Problem
When running Zoom on a Lenovo W540 laptop the webcam was not working despite the indicator light being active. In Zoom the webcam icon looked as if it was disabled. The laptop was running Windows 7.
Solution
Close Zoom or any programs that might use the webcam.
Then go to Control Panel > All Control Panel Items. Open “Lenovo – Web Conferencing”.
Click “Show my video image”.
Close the “Lenovo – Web Conferencing” application. The camera should now be working.