To gvarnell,
Does your two wifi routers have a long name with the same characters for the first part of the name?
Example:
Router1 SSID = "Johnnie_Appleseed's_wifi_2.4GHz"
Router2 SSID= "Johnnie_Appleseed's_wifi_5GHz"
if iOS7 for some reason only recognize the first part of the name, then the ipad would not be able to join either network reliably.
Remove the apostrophe from the router's SSID and the iPhone's name, if there is one. Shorten the SSID name.
Do not turn enable 40MHz channel for 2.4GHz router.
Turn off one router first.
Do enable WMM.
Security for 802.11n is now required to be WPA2-PSK AES (not TKIP anymore)
Is the iPad5's IP address fixed on the router? If yes, remove it, try joining again.
Or, try setting fixed IP address for the ipad 5 on the router, and set same IP on the ipad5.
Power cycle the router to flush out the dhcp table.
You said ipad 5? Are you refering to the newly released iPad Air?
Upgrade to ios7? It should come with ios7.
I find this part a possible cause of wifi logon trouble:
http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol
"A DHCP client can also request its last-known IP address (in the example below, 192.168.1.100). If the client remains connected to a network for which this IP is valid, the server may grant the request. Otherwise, it depends whether the server is set up as authoritative or not. An authoritative server will deny the request, making the client ask for a new IP address immediately. A non-authoritative server simply ignores the request, leading to an implementation-dependent timeout for the client to give up on the request and ask for a new IP address."
If the ipad retained its last IP address over the upgrade to ios7, it'll request it's last known IP address. Now if the router uses the non-authoritative server method of ignoring the request, but let's suppose Apple's implementation has a very long timeout, the we could see an idevice not being able to join the wifi network.
Best regards.
