I NEVER had to do anything with the IGMP or such. https://itunes.apple.com/us/app/chromecast/id680819774?mt=8 shows the app to set it up.
Next time try your router's default settings.
I've never had to change them.
Bob
I am attempting to set up my Chromecast. I have a Vizio TV. My wireless router is a Motorola Arris SBG6782-AC... I am using my iPad air 2 running on IOS 8.1.
Here is what I have done:
- Enabled: Universal Plug and Play (UPnP), multicast
- Disbaled: AP/client isolation, virtual private networks (VPNs) and proxy servers
- Restarted my iPad, Chromecast and router several times
The instructions also mention enabling IGMP and disabling IGMP proxy but I have no idea what that is or where to find it.
When I try to set up Chromecast it states that it has connected to my network but cannot connect to the internet.
What am I doing wrong?

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