I have a group of .jpg images from the same source that all seem to behave fine: I can open/edit them with eog/Kolourpaint/GIMP, their thumbnails load correctly in Nautilus, etc.
However, when I try to upload these images (through a web browser onto Tumblr for instance), one (and only one) of these does not preview in the Nautilus file upload browser, and Tumblr returns an error when I try to upload this file.
What kinds of issues would cause an otherwise well-behaved jpeg image to not preview in the Nautilus file upload browser?