Hi JAC7031
I am Dave, an Independent Advisor, I will help you with this . . .
On the View ribbon, in File Explorer, turn on 'File Name Extensions'
On the files names of those files, is the file extension just jpg or is there an extra character after jpg?
If there is an extra character, right click one of those files and choose rename, remove that extra character and then see if you can open that file
If not, right click one of those files and choose Open with - choose another app and select Notepad
Please provide a screenshot of the start of that file in Notepad . . .