There were some users which could display some image on their PC but such image could not by manage by GD on the server. Really no idea, but maybe GD does not only display the image but it must work with it, so if there is some small error, you can display the image on your PC (I can e.g. display corrupted jpeg - it only display half of the image and the second half is grey) but you cannot manage it in GD ... maybe, really only my ideaI 'saved as' and the error is still there. However, not sure what's wrong with the files. For these files open correctly on my computer, both in preview, photoshop or any other software
Jan