I am having the exact same problem as doggfather. I was able to FTP to my xbox a few months ago. I don't know if windows update SP2 has anything to do with it, but this seems to be the only thing that I have done to my PC lately. Anyone have any ideas?
A co-worker of mine suggested that when I turn on my xbox, that I should go into the xbox media player program to ftp instead of simply sitting on the main dashboard screen. He swears that it ftp's faster than on the main evox dashboard screen. Can anyone confirm this? I'll try it when I get home from work today.