I selected File > Import > Images as Planes, and chose a 700 kB png from the file system screen that pops up (in Blender 2.76). The first time nothing happens, on later tries it gives me the errors shown in the screenshot:
I've tried now with different images, same thing. Definitely nothing is added to the scene - nothing shows up in the Outliner. It is a new file nothing in it but a lamp and a camera.
Edit: This was a temporary problem with the Ubuntu launchpad ppa version of Blender. It has now been fixed.
The file is here
The png file can be downloaded from here, and here is a version: