Apple TV connect to network, but not recognised by Imac

[Bulldog VII]

Hi all

I'm pulling what little hair I have left out!

I recently upgraded to 10.11.1 on my imac (3.2Ghz Intel Core i5). For some unknown reason now I can't connect to Apple TV via my wireless network (BT home hub 5). My printer is also not recognised.

I know that both the apple TV & Printer are connected, as my partner can print wirelessly from her PC & we downloaded & watched Ted 2 via my Apple account. I can also use Netflix. For someunknown reason the imac can't see them? I also connect to my home hub wireless via the home hub, so I know that's on the network (the Imac)

The problen seems to have occurred once I upgraded to El Capitan. It was fine before. I have done all the available updates via 'App store'. When I updgraded the imac used to automatically connect to the free wifi that BT offer to it's users (bt fon), I presume it got the password for this from my iPhone? I have to manually change the wifi network to my hub??

Running out of options & any help would be appreciated

Does anyone know how to reset the wifi settings??

Thanks

 

[westrock2000]

Your iMac is connected through WiFi or hardline? Can you access the WiFi router from your iMac? Usually something like 192.168.0.1. Your iMac has a similar IP address as other devices on the network? Subnet mask is set to 255.255.255.0 or whatever everything else is?

 

[Bulldog VII]

My imac is only connect via the wireless network, the router is the other side of the room so can't be plug in via an Ethernet connection. Yes I can access the router via the imac & i don't understand what you mean by Subnet. (Can you imagine you are speaking to an idiot & you'll get my level of compitance on computers!!)

 

[priitv8]

Subnet mask is part of network settings:
http://www.macworld.com/article/2027960/configuring-your-macs-network-settings.html

 

[GlenK]

Since upgrading to ElCap my Airplay icon in the menu comes and goes, but mostly goes. Have tried everything and so far nothing has lasted. Very frustrating.

 

[priitv8]

Very helpful tool to see what's bugging Bonjour is BonjourBrowser

 

[waw74]

try rebooting your router and network gear.