I kept getting the above message when trying to setup on my windows7 after downloading the app. No firewalls, no vpn on my pc. I am using a dlink wifi card on my desktop pc. I tried on my Andriod phone and got the same error message. Funny thing is my colleague tried on his iphone and it works! So what could possibly be wrong with my windows setup ? I don't think its a router/modem issue. Already tried swapping 2 wifi cards, reset the Chromecast, and placed the pc just next to the Chromecast.