If you tried watching Nasa TV in my last post with Silverlight, you'd find that it wouldn't work. And once again the problem is with the ASX file - to be more specific, the exact same problem I had to find a quick fix for last week for Moonlight.
The ASX file I linked to links to another ASX file. This second ASX file has a copyright symbol in it (©), and it stores it in the CP1252 code page (i.e. the binary value 0xA9 - this is an illegal value in utf8). Now it seems like Silverlight expects the file to be in utf8 , and it errors out if it isn't .
Unfortunately I can't link to the real mms link, Yahoo seems to uses some sort of authentication ensuring that you got the link from the ASX playlist.
I notified Yahoo using their contact form about this, asking them to fix their ASX output, now let's see what happens...
 When there are no byte-order markers at least
 Windows Media Player plays the ASX file just fine.