Well it depends on what device the SD card was in when the photos were put on it. You didn't list a device.
You should actually place the SD card back in that device, and then, if it is a tablet or phone, connect it to a computer via USB cord and try viewing them that way.
If you are trying to access them by placing the SD card into a computer, you should try moving them off the SD card onto the computer (in a folder) and then see if you can open and view them from there.