I had the same problem with my 536. Check your SSID settings. When I shared the same SSID with 2.4G and 5G on the router, it caused an issue with the 536 connecting. Once I split the SSID's and changed the name of the 2.4G network, connection resumed.
I could scan and see the WiFi network. I was just unable to connect with the network, even with the correct password.
Note, this is a setting in the router to share the SSID and allow the router / device to pick the best network. I did not manually choose to set both SSIDs identically. For whatever reason, sharing the SSID between both layers caused a problem for the 536.