I've tried resetting network settings, made sure router has latest firmware and done a full restore to my iPhone, still won't connect and if it does manage to connect, the connection falls out after a couple of seconds and then the phone refuses to find any WiFi.
Would be so much nicer if Apple would,d let me roll back to 8.2 when everything worked. I've updated to 8.4.1 in the hope that Apple would fix this problem, some hope, maybe they aren't really interested in fixing problems on older iPhones, hoping people will upgrade to newer models.