Hello, thank you for reaching out to Microsoft Q&A.
The error appears if the computer no longer detects your camera. This can be a driver issue or a hardware issue.
- Open the Device Manager.
- Expand the arrow next to Cameras to expand it.
- Right-click your integrated camera driver, select Uninstall device, select the Attempt to remove the driver for this device check box, and then select Uninstall.
- Once uninstalled, restart your PC and open the camera app.
If you’re still experiencing issues, please make sure your camera isn’t blocked by anything such as a shutter or cover. If your device has a physical switch to turn the camera off, ensure it’s turned on.
If the problem persists, type msinfo in the search bar on your taskbar and press Enter. Then, please share a screenshot of the window that appears.
Let me know how it goes.