Saw this on another post :
"I fixed mine, it may help others that are scratching their heads as to why it worked before firmware update not touched anything else but now it doesnt work
At home I'm on Virgin, I have a Netgear Super Hub 2 being used as a modem and a Netgear NightHawk 8000 router, I noticed on the router the DNS was NOT set to automatically get from ISP, changed it to get from ISP automatically and now on the NOW Tv box i get 3 green ticks and i can access the app store."
Same for me - my router had manual DNS setup for OpenDNS/Google but the only way I could get the stick to work is to change it to Automatic and use my ISPs? - this shouldnt stop the stick from working but it does!!!