I too lost my WIFI capability after the last upgrade, not the 8.0. It has been over a month that I am forced to use data or turn it off when i dont wish to use it but then risk not getting all of my text messages. I have tried doing all the recommended changes/actions in order to get it working again but nothing thus far has worked. Apparently this is a know issue and Apple simply doesnt want to take the responsibility of correcting the issue or offering upgrades even if your not due for an upgrade for any length of time. Not very happy with the I-Phone at this point. They want you to upgrade your phone at your expense or pay that stupid monthly fee for a phone which will end up costing you the same amount as the phone and then you have to give it back...How is that fair to the consumer???
You first go into your device and if the network is showing click it and select "forget network"
Turn off the iPhone completely, keep it off. Now
Go over to your broadband modem and unplug it.
Go over to your wireless router, unplug it.
Wait a few minutes. Then turn the broadband modem back on and make sure its all cycled back up.
Then do the same for your wireless router. Make sure its fully cycled on and stable.
Now turn on your iPhone/iPad and wait for it to fully load up.
Click on WiFi and see if the device finds your network.
Click on your ssid and enter your password.
You should now be connected and hopefully will stay that way
Good Luck to both of you.