Yes I ran the application and have attached a screenshot of the resulting window. It did not, as far as I can tell, produce any kind of file.
Also, there seems to have been some wires crossed? Why would I want to convert my AVI files to MP4? I don't really use Windows Media Player - it's bulky and incongruous. I was using DivX player but have switched to VLC.
I apologize if I didn't make myself clearer, it was very late when I was writing this.