0xA00F4243 – Camera may be used by another app

The camera may be occupied by another program or may not be able to start.

Stop if unsure or if a new warning appears. Save your work before changes and ask IT before changing a work device. Never disclose passwords or recovery keys.

Close other video conferencing apps and browser tabs with camera access.
After saving, restart Windows and first only open the “Camera” app.
Check camera permissions. If only one app is affected, select the correct camera there and update the app.

Test after each step and stop when the issue is solved. Checkmarks are not permanently saved.