From Reddit: "I have been using Shotcut for a couple of months now and I have experienced a few issues with it. I don’t remember having these issues before, until now.
First off, I am getting a message when I try to upload an image brought up from my phone, it just says something like “Failed to Open C:/Users/Owner/Appdata/Local/Temp/20210…”. Does anyone know about this?"
I think the problem is in the bringing it from the phone.
Try doing this in steps; first bring it to a folder in your permanent spaces, then verify you can open it, view it there using Windows apps, then, try bringing it from there into Shotcut.
Ok, everything’s good now. I had to check a few boxes off the Shotcut update page to finally access Shotcut, and everything’s good now. I relocated my media files in a new file under ‘Videos’. Thanks for your help @kagsundaram!