AppleTv2 not connecting to homesharing after yosemite update

Hello,

I always keep my Imac up-to-date, and after the last system upgrade (Yosemite 10.10.3) my AppleTv (2nd generation) is not connecting to the itunes library.

I checked everything, restored appleTv, activate and deactivate home sharing (on AppleTV) but nothing happened. Then I checked iTunes on the iMac and instead of finding "Family sharing" now the service is called "at home". I don't think that a different name means a different service obviously, but for some reason now my appleTv now is not connected to my iMac.

Also on the mac I stopped and restarted the service, checked the account, both user and password, and in theory everything is ok and should work as has always done...

Both the iMac and AppleTv are on the same wireless network; I checked also that, disconnecting and reconnecting to the network.

May be that there is some other thing changed and I was not able to understand?

Does anyone have a similar problem?

Thank you for any help.