First, let me give you a couple of pieces of info about your UbuntuForums posting that you might not be aware of. I imagine you gave us a link to the thread because LQ doesn't allow you to upload anything. None-the-less, people have to log in to view that image at UbuntuForums, which means only UbuntuForums members can view it. (Fortunately, I am such a member. Not many posts over there, but I can login.
The other thing is that image takes a *very* *long* *time* to download over dialup. Only a small part of the image contains the actual information you want people to see. It would have been much better if you had taken an image of just the window with the error message.
But back to your problem ... That message appears to be a security warning that the content of the file does not match the extension for the file. Perhaps you should post the contents of the file.