Internal Picture Viewer and zero-filled .JPG file

I have encountered problematic .JPG file and I've decided to use Hex View function of DOpus Picture Viewer to look what is inside that file. When that file is opened a message "Unable to load 'IMG_0004.JPG" as a picture" is displayed. When I click on "Hex View" button, viewer's window disappears.
I was able to hexview that file using other method. First I've opened a correct JPEG file, then switched to Hex View, and then I've opened IMG_0004.JPG via menu function File/Open... . It appears that the whole file is filled by zeros.
In case that information would be needed to reproduce the behaviour: file size is 2 643 971 bytes.

Directory Opus Pro 11.16.1 (Beta) Build 5770 x64
OS 6.2 (B:9200 P:2 T:1) SP 0.0

Was it the only image file in the folder?

If an image file can't be loaded and I switch to hex view, I get a hex view of the next/prev file in the folder, since it triggers loading a file (none is loaded when an error message is displayed) which causes it to move on to the next valid file. If there isn't another file then the viewer would close.

I did not knew that such closing is intended behaviour.

There was:

IMG_0004.jpg (zero-filled)
IMG_0025.jpg (correct)

in the same directory (and some non-picture files and dirs).