The issue arises when the user suddenly gets a message that Photos Media Engine Add-on is installed after connecting a USB device (with photos) on it but the user cannot find/uninstall the Photos Media Engine Add-on like a normal program (from the Control Panel/Settings). You can try the following solutions to remove the Photos Media Engine Add-on but before that, make sure the Windows of your system is updated to the latest build. Also, make sure all the Windows Store apps (especially the Photos app) is updated to the latest build.
Solution 1: Uninstall the Photos Media Engine Add-on from the System’s Settings
The Photos Media Engine is an add-on to the Photos app and you may uninstall it from the system’s settings.
Solution 2: Use the PowerShell (Admin) to Uninstall the Photos Media Engine Add-on
If the issue reappears after uninstalling the add-on, then you may use the PowerShell (Admin) to get rid of the add-on but it may uninstall the Photos app altogether. If the issue persists or the add-on reappears, then you may have to stop the Exe file of the add-on from launching (be extremely careful, as these steps may cause non-recoverable damage to your system) but you may have to take ownership of the installation directory of the WindowsApps folder in the system’s drive. You may disable the inherited permissions, remove all the permissions except read/write for your user account (make sure to replace the permissions on all the child objects) for the Add-on folder (in the WindowsApps folder).
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