Now that we've verified that all of the network settings are correct, it is time to start troubleshooting the WiFi connection itself. The first thing we'll do is to reset the iPad's WiFi connection. Usually, this simple step of telling the iPad to reconnect will solve the problem.
We can do this from the same screen where we verified the settings. (If you've skipped the previous steps, you can get to the correct screen by going into your iPad's settings and choosing WiFi from the list on the left side of the screen.)
To reset the iPad's WiFi connection, simply use the option at the top of the screen to turn WiFi off. All of the WiFi settings will disappear. Next, simply turn it back on again. This will force the iPad to search for the WiFi network again and rejoin.
If you still have problems, you can renew the lease by touching the blue button to the far right of the network's name in the list. The button has a ">" symbol in the middle and will lead you to a page with the network settings.
Touch where it reads "Renew Lease" towards the bottom of the screen. You'll be prompted to verify that you want to renew the lease. Touch the renew button.
This process is very fast, but it could correct some problems.