Can't upload files - "Empty files cannot be uploaded"

New account. I cannot upload any files (JPEG's). I get the same message every time that I can't upload empty files. I am trying to upload from my PC. I've tried Chrome and Edge, same result. I've cleared my cache, same result. I've searched this community and the net for clues, to no avail. Any ideas?

Update: As soon as I posted this question, I realized what my problem was. I was trying to upload from an "extraction" folder before the files had been extracted. FACEPALM!