After trying every solution on the web without results, I stumbled on a solution that worked for me.
We know the error results from the camera trying to save pictures to the "Camera Roll" folder and failing for some reason, (Folder permissions, location, camera drivers, etc)
After trying all solutions including resetting the camera app and uninstalling it via PowerShell and reinstalling, I went into file explorer and highlighted my C:\ drive, ran a search for "Camera Roll" and was surprised to find more then eight copies of
the folder or the history of the folder in various locations on my hard drive.
I deleted every instance of this folder that I assume were created by the last major Windows 10 update since the camera was working fine up to then. Most folders deleted easily, some didn't. Those in the "App Data" folder would not delete but were called
"App history" anyway.
Then I went into "Apps & Features" in settings, clicked on "Advanced options" beneath the Camera app and reset the Camera app. This re-created the Camera Roll folder where the app could now write to it with no interference from identical folders elsewhere
on the C;\ drive. I then tested the camera and it's working fine again, finally!
I hope this helps others with this frustrating problem.
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