File format cannot be opened

I have saved all my 9500 photos from my Iphone 5s to my Macbook, I have then saved the pics to my 2TB WD exFAT hard drive, I also use a PC and wish to open my Iphone pics on there, when I try to do this my PC informs me the file format cannot be opened, upon opening the folder the images appear in the icon for a brief second but then the icons go blank and then I get the format message when I try to open.

I can still access my Gopro footage through Adobe Premier Pro CC from my PC and Mac Book. I often save files from both machines and re open between them with no issue. I have no clue as to why the PC won't let me open them.

I also had a message saying my PC was blocking me from opening the file, I tried disabling Norton but still the problem continued, I have performed a windows update checked for errors on the hard drive but still no luck.

I've rebooted the machine and swapped USB port, all that happened when I did this is that the error message changed to cant open that format.

Is it my Iphone my Macbook, WD or my PC?

Any ideas, its driving me crazy!