Decode error! JPEG datastream contains no image.

Storing to memory card. Five of seven photos just fine. Two appear fine in size and look great when Reviewed through the camera, but when I copied them to the pc hard-drive (and also straight from the SD card) the error message is: Decode error! JPEG datastream contains no image. .... or, File format is not recognized by this software. I've tried LView Pro, Irfanview, Wildbit, and Picture It! All give similar messages. These two photos are from a special trip yesterday and very important to us. Can anyone help me salvage them? (I'm a grandma who does okay with computer stuff, but have no formal education on them or anything). I sure do want those two photos. Don't know why it happened! The 4 before and 1 AFTER that are fine!