This issue is caused by a bug in the Windows 10 Update that either resets or tries to reset the default app back to what it originally was usually to the UWP apps. The reason why Windows 10 does this is because, it thinks that the third party application changed the file associations by incorrect methods. So Windows resets the file associations default apps. An app default was reset. An app caused a problem with the default app setting, so it was reset. If youre experiencing this issue, you...

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