I thought I had te same error. I updated whilst at work on my lunch break but once home I couldn't connect to my home network. I deleted it, re-booted and setup the wifi again but still no joy.... that is, until i noticed my battery was quite low. I connected the phone into my laptop to charge (note, the laptop was currently connected to my home wifi perfectly!!) and then while it was charging I tried to connect again and this time, it connected fine. Once the phone was more than half charged, I removed the USB cable, disconnected from the wifi, and then tried to connect again. It did.
I'm wondering maybe some functions are disabled if battery is just too low? If not, then maybe just an odd little issue!