If you are on a notebook with a integrated camera, try connecting an external camera.On that other PC you may also need to do the solutions presented above. If you have an external camera, check it connected to another PC or try with a different camera on your current PC.
Check "Disable all automatic Windows driver updates from installing" from this guide on how to do this.
If you are on Windows 10, you should prevent Windows Update from updating the drivers, as at some point it could load the buggy drivers again.Click Next, and wait for the confirmation that the drivers installed correctly.Within the browse window navigate to the folder where you have extracted the driver files from the downloaded archive.Choose "Browse my computer for driver software" and in the next screen select Browse.Go to Driver tab and and click on Update Driver.If your camera already has drivers installed, look under Cameras or Imaging devices categories for the camera and If it does not, it will show up as a "Unknown device" or similar and has a yellow icon with an exclamation mark.Launch Device Manager (press Win+R or search and copy-paste: devmgmt.msc or right-click on This PC/Computer icon > select Manage > select Device Manager).
Extract the files if the driver files are placed in an archive (.zip.
Others may require you to manually install the driver through Device Manager:
You could try to disable all other devices but one at a time (with right click -> Disable) and retest the camera in an application (close and reopen it each time you try), you can keep the Device Manager window open.
For Discord: User Settings > Voice & Video.A couple of examples where these settings are in different applications:.If camera works in the previous steps, open that specific application that does not work, go to it's settings/preferences and check that under Camera/Video device the proper camera device is selected.