The image is way too big (you have a 125 x 125 px max limit), and it's missing an image file extension so it may not be recognized as an image anyway. I took the liberty of resizing it for you though, blending the background in a little more and uploading it to an image hosting website.
Please try this and let me know if this works!
http://i61.tinypic.com/339r7gl.png