I've added a few images to my blog using the new Media Library tool without much trouble but I'm currently seeing a strange issue. Two images that I upload do not generate mid-size or thumbnail versions.
It uploads the original and uses that image for the post. Whether I insert an image as thumbnail or with the [gallery] quickcode, I get the full size version only.
Looking at my upload folder, I see there is no mid-size or thumbnail version of these two files like there are for other images I've uploaded.