I have just purchased a Sandisc Ultra USB and backed up my PC.
When I put the USB into my PC and I open the photos folder it does not show the thumbnails, only the icons. I would like to be able to view and browse the thumbnails through my PC to choose what to transfer and view.
Previously I used a Integral Courier USB which allowed me to do this. I chose the Sandisc as it is password proteceted.
Don’t know about other USB drives but your SanDisk problem only applies to the use of SecureAccess for your pictures. If you save the pictures to the USB drive directly, outside the SecureAccess app, you will be able to see their thumbnails.