Home sharing will NOT allow sharing.

Yes, as Wooroonden mentioned, a dedicated router will solve your problems and I highly recomment that you go that route.

You don't need much. If you are on a budget an AirPort Express will do the job but be aware that it only includes one LAN port. If you need to connect more than one device on the network using ethernet then you will need an AirPort Extreme which includes 3 LAN ports. If you need more than that you can add a network switch.

Routers by various third parties will work as well but aren't as elegant to set up and many suffer from the UPnP bug that exposes them to hacks from the WAN side and others suffer from the WPS bug that exposes there wireless network to hacks.

http://www.grc.com/su/UPnP-Exposed.htm

https://community.rapid7.com/docs/DOC-2150

http://www.kb.cert.org/vuls/id/723755

I'm not sure what you mean by:

CAN get AIRPLAY to work, which is computer to computer, Itunes being on the Imac and the music playing through the ATV.

as by AirPlay, I mean using my iPad or iPhone to connect directly to the ATV to play content (movies, photo slideshows, music etc.) - directly from the iPad/iPhone to the ATV/television screen. This is different to playing something from the computer to the ATV.

http://support.apple.com/kb/ht4437

I agree that the third party ones are not 'elegant' to set up! Now that you mention 'bugs' I am thinking of getting an AirPort Express to replace the one I have!

What I mean is that on my Itunes, on my IMac, there is a choice, titled Airplay, where you can tell your computer, my IMac to play the music on the ATV. On the ATV I can tell it to accept a connection from the computer to play the music on the computer using the TV speakers. And when these are set, voila, I can go to my computer select my music to play, and the ATV will play that music.

BUT I can't use my ATV controls using HOMESHARE to choose which music to play, so I am always running back to the computer to change the play lists.

But don't you use your Apple Remote device to do the choosing with your ATV?

That my friend is exactly the issue. The ATV remote only works to tell the ATV what to do if the ATV can connect using HomeShare, which it won't. The Airplay option on the computer can tell the atv to play the music the computer provides to it, and the album cover will show up on the atv and will play the music, but cannot control the computer.

I forgot! So I guess we are back to your needing to have both the iMac and ATV connected to the same network via a shared router.

Thank you for contributing to this discussion. Regarding Home Sharing, my wife's iPad is under her own Apple ID and it still allows my iTunes library to share but the data is almost always disorganized: sort fields are wrong, few artists displayed, wrong artwork, etc. Is this due to the fact that she's a separate Apple ID? Any way to fix it that you know of? Thank you.

I believe I finally resolved the issue, at least on my PC with Windows 7. After much research off the Apple site, I saw a suggestion to disable IPv6 in the network adaptor properties. I did this and a reboot later Home Sharing began working properly. Not sure if this is something Mac users can make use of, but it seems to have worked for me.

I believe the issue is with iTunes 11 as Home Sharing worked fine for over a year without me having to make this change. I only started having issues late in 2012 after the new iTunes was released.

Hi Mike, I had the same issue with "Homeshare" My entire ITunes library resides on my windows 7 machine and I purchased my Apple TV 3 months ago. Apple TV worked fine for me right out of the box for a couple of days and then Homeshare started disconnecting after placing a video load on the network. I was using a Cisco router at the time and started tweaking my settings but no joy. I figured that its and older router so I purchased an "Airport Extreme" and no joy there either. It occured to me that I saw this issue before using peer to peer D/L where the network had a throttle down and would slow down and kick out. SO I disconnected windows firewall and have had no issues for several weeks.I went to "Shields Up" to see if I had any vulnerabilities and the hardwired router firewall has me protected.

Update. It's been a month since I posted the above and so far, it is still mostly working. The "AirPlay" control always shows when i open iTunes now. A few times, my Apple TV hasn't shown up as a choice, but a simple reboot of the router fixes the issue.

having the same problem, what did you do????

so after 6 months my apple tvs will no longer recognize my imac itunes library - tried reset, restart and on of switch - i notice my apple tvs are not mentioned in icloud account devices as per your advice above. Should they be and how do I get them in there? M

I have the same problem as you had. Can you possibly tell me what you did to remedy this? I haven't figured it out!

coming into this thread today, describe your issue for me.

iE: Equipment, homeshare from what? PC , Mac etc.