Why can't I access iTunes from Apple TV!

My apple TV 1st gen recently can not access Itunes. I can not purchase music or music videos. Some videos will download for preview, but most won't. I can not get music to preview. I get the message: iTunes is temporarily unavailable. Try again. It has been like this for about a month.

If I purchase something on my Mac book pro it will sync with Appple TV and play. I think this has happened since I upgraded to lion.

I run parallels on my Mac but that has never been an issue before. I have been able to purchase music in the past. What could be the conflict?