Originally Posted by Vetinari:
“Humax are hopeless with JPG's.
I tried some on my Foxsat - they could be viewed and edited on PC's, macs, and Linux but the Foxsat said it couldn't understand the format. Pathetic.
I was able to see they existed, though.”
The problem is possibly related to the presence of Exif tags.
Try using a editor on one of the files without making changes.
Wikipedia:
"Problems > Technical
The Exif format has a number of drawbacks, mostly relating to its use of legacy file structures.
The derivation of Exif from the TIFF file structure using offset pointers in the files means that data can be spread anywhere within a file, which means that software is likely to corrupt any pointers or corresponding data that it doesn't decode/encode. For this reason most image editors damage or remove the Exif metadata to some extent upon saving"
I found this worked for all my JPEGs.