JPG is a common file type for pictures. I am not sure why you cannot see them -- have you tried using "Paint" (included with all Windows before 10)? What kind of error do you get?
The link might help you. Let us know what helps you
Thank you. When my son in law has time I will have him try this link. He does all my computer fixings Will let you know if it works,
I just double click on it and it opens. To have it show a thumbnail in Explorer set the file to Large Thumbnail. Can't show you a useful picture as my Windows is set to Dutch.