Apple TV works with my iPhone but not with my PC on the same wireless network I have:


Windows 7 PC with latest version of iTunes connected to my network (wired). Windows Firewall is turned off.
Apple TV (2nd generation) connected to my network (wireless) 
iPhone connected to my network (wireless)


I am able to AirPlay from my iPhone to the Apple TV, but it does not work from my PC.

In the Apple TV menu under Computers, I can see my computer's library but when I try to connect, it takes a while and then it fails. I don't see the Apple TV from iTunes on the PC. (I don't see the iPhone either under sharing but I don't know if it should show up there or not).

I don't think it's a router issue otherwise it wouldn't work with the iPhone either.

I have reinstalled iTunes on the PC and rebooted all devices (router, PC, Apple TV).

What do you think could be the problem?
This sounds like a home sharing issue to me. I would check that the Apple ID you have set in iTunes on your PC matches the ID you have configured for home sharing on the Apple TV and that the password is correct for both.