Hello, I'm Greg, here to help you with this.
It sounds like Movies & TV player has lost it's default to the new Media Player. This may be due to an Update. I'll show you how to change it back or if that doesn't work how to troubleshoot the error you're getting or repair Movies & TV app:
1) Check in Windows Settings > Default Apps > Set default by App > Movies & TV, change Media Player to Movies & TV app, Set as Default. Now try opening a Movies & TV video again.
2) Try these fixes for the error Windows cannot find:
https://thegeekpage.com/fix-for-windows-cannot-...
https://windowsreport.com/fix-windows-cannot-fi...
(Avoid ad links which intrude into editorial copy, especially DO NOT INSTALL Restoro, PC Repair Tool and Reimage ads)
https://www.youtube.com/watch?v=NNN7AWxKr4A
If those don't help then 1) Try these fixes first for Windows 11 Movies & TV app not working:
https://www.videoconverterfactory.com/tips/movi...
https://www.makeuseof.com/windows-11-films-tv-fix/
https://www.youtube.com/watch?v=7v8AhRFNZjE
3) If those fixes don't work then try these fixes first for Windows 11 Movies & TV app not working:
https://www.videoconverterfactory.com/tips/movi...
https://www.makeuseof.com/windows-11-films-tv-fix/
https://www.youtube.com/watch?v=7v8AhRFNZjE
3) If those fixes don't work then Go over Windows 11 with this Performance Checklist to try to find and fix problems:
https://answers.microsoft.com/en-us/windows/for...
Feel free to ask back any questions. Based on the detailed results you post back, I will have other suggestions if necessary.
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