There are no fewer than 682,000 posts on "apple tv not recognized in itunes" in a Google Search. This has been an ongoing problem with Apple TV devices since their inception. Apple does not care. Apple gives bad support. There is no reliable solution, except to use some other device (WDTV, cheaper and more versatile). However, Apple TV Gen1 has one unique advantage that NO ONE else has . . . the floating picture screensaver. To my knowlege, there is no device capable of displaying more effectively thousands (Yup, that's what I got) of photos on an HDTV with music playing during a party. So, now that I stupidly "up"graded to itunes 10.whatever, it doesn't work. Steps taken:
1. Connected by ethernet
2. Accesses the web and Apple Store (plays movie trailers) no problem
3. Turned off firewall
4. Turned off router security
5. Reinstalled iTunes
6. Factory Reset/diagnostics on AppleTV, unplugged and replugged
7. Rebooted numerous times
8. Restarted with all services and startups disabled except for Bonjour, Apple, iPod and iTunes services and programs
Aaaaaand none of it helps. Why not? Because of buggy malware distributed by Apple. It's why, despite Windows getting progressively worse since XP, I refuse to switch to Apple products. So far there's not been a Windows problem I can't fix with enough looking on the web. But when 682,000 posts suggest a problem that has not been addressed since it was first sold 5 years ago, well . . . why would anyone want an Apple product?
This is a repost of information gleaned from somewhere on this site. I couldn't find it again, but I wanted to say thanks! Your suggested link for solution worked. ITunes 10 via Windows XP now recognizes my IPhone 4. Here is the link reposted (not sure how to do that here, so copy and paste in your browser if necessary--I'm not the techy one...)
http://support.apple.com/kb/TS1567
I ended up having to use the third solution, which was to unload all ITunes/Apple related applications from my PC, then reload ITunes 10. It worked!
TBera

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