I can't add contents to projects

I’ve just downloaded ShotCut for the fisrt time on windows 10 pro; I can’t add or open any contents to the projects, I’ve tried with mp4 and jpg:

could you tell me why? Thank you very much

That screenshot doesn’t really show anything.
You say you can’t add or open anything. What happens when you try to add or open video or images?

Shotcut don’t add to the project and don’t open the clip, and says “impossibile aprire:::” , i.e. “impossible to open…” (I have the italian version)

Can you post a screenshot of that?

Try putting your media on drives other than A or B.
Can you load all of your files from a different drive?

from C it’s the same…

Is the file open in another program?

I do see you have two instances of Shotcut open.
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Can you get the file to play or show in video player like VLC?

I’ve tried with many files, not opened in other programs, all of them I can play with video players, all of them I can’t open in Shotcut. I’m desperate!