Cannot connect to hidden network

[AC Question]

Just got a HTC One M8 and everything is amazing! However I can't connect to my home wifi because it says 'out of range'. I manually typed in the SSID and security and moved the phone closer to the router but nothing seemed to work.

How can I get it work? Please help!

 

[STARGATE]

Cut the power to the router for a minute, turn it back on.
On the phone, clear cache, soft reset the phone.
Try connecting to the network now, see if this helps.