Can you open the files using Arcsoft? I have that software also and it defaults to that file extension when you save pictures. You have to change the file type every time you save anything. Install the program and see if it works. If so, save all of them with a .jpg or whatever format you prefer. Arcsoft will give you a pop up with a warning about changing the file type, but I have never had a problem. Test on a few first before going all out.
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