Hello HannHann1,
Good day! I'm John Dev a Windows user like you and I'll be happy to assist you today. I know this has been difficult for you, Rest assured, I'm going to do my best to help you.
Please try Shawn Brink's tutorial guide below on How to Restore Windows Photo Viewer in Windows 10 if it helps.
https://www.tenforums.com/tutorials/14312-resto...
Kindly let me know if this helps or if you have any further concerns.
Kind regards,
John DeV
Independent Advisor
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