Nighthawk XR500, EX7700 & EX7000 Network setup issues

Hi, 

So me again. 

I'm getting to the point where i feel spending £600 on Netgear stuff is a waste of time for seemingly awful prducts that don't do what they say.

My XR500 seems to work ok mostly. I bought a EX7700 extender as the XR500 range is about 10m tops so that is sat around 2.5m away and connects wirelessly ok and extends to an ok range (about 10m).

I have recently had my garden renovated but the internet coverage is poor (about 15m range) so i planned to put another extender in my shed at the end of the garden (i have a prewired CAT5e connection). I purchased an EX7000 extender and set this up as an access point. 

Everything seems to set up ok, passwords all gone in fine but the EX7000 simply say 'no connection' next to both 2.4 and 5ghz networks. The ethernet cable works perfectly wired.

Can anyone help please?

Thanks.