Thank you very much, this is exactly what I was looking for. Just minutes before reading your message, I also thought about the same. Based on the edition I have, it makes sense that I was not able to install what I downloaded.
The funny part is that I downloaded a 1.5 GB file earlier today and when I go back on MS site, the only thing now I see is DVD edition which are way over 4 GB. Is it me or they just removed the non DVD editions from the site this afternoon?