I\'m working with a SharePoint site in O365. The site includes a List/Library that contains nothing but employee images with .GIF extensions. A 3rd party process imported
My Solution:
If I opened MS Paint, created a new .GIFF image and saved it to my server, it would actually display properly.
This led me to use ImageMagick and do an identify on the images that wouldn't display. ImageMagick indicated the images were originally PNG's and were saved to my server as GIF's for some reason. Renaming the image files back to their native format via a workflow resulted in them being displayed properly. So, whatever process uploaded all the images to my server renamed PNG's to GIF's, messed up the files and resulted in this problem.