*SOLUTION* No Wi-Fi after iOS6 install ! > READ ME<

I went to the connection and just clicked "renew lease" and all was back to normal.

Settings>wifi>your connection then click "renew lease"

If you are having the issue where it takes you to a login page, goto Settings > WiFi and tap on the blue button to the right of your network name. There'll probably be an option to auto-join and you'll want to toggle that. If it's off, turn it on then back off. If it's on, toggle it off. If prompted to login again, just hit Cancel in the upper-right. Now goto Safari app and you should be prompted to connect to your network at which time it should work. It did for me at least and a friend of mine.

I found waiting for all wifi networks to be found then selecting the one you want works. No other changes (proxy etc) needed. Tested several times with several people.

this worked for me:

This is how to properly restart your iDevice:

- Hold both buttons (top and bottom) at the same time for around 10 seconds until the screen goes off.
- Immediately release both.
- Press top button until Apple logo shows up.
- Wait forever until device comes alive. (This REALLY does take long time, but do not worry)
- Bingo, your network problems should go away.

Worked for me

It will start working. Something happened at 6pm CST and lasted about 40 minutes. Just keep trying to connect. I did not have to do any resets/fixes.

FIXED https://discussions.apple.com/thread/4312572?tstart=30

You're talking about a restart but give steps to reset the iPhone. The steps you provided are similar to pulling the power plug to your computer instead of shutting it down properly. While doing it when the computer (iPhone) is unresponsive would be fine, consistently doing this will corrupt your files.

The proper way to restart the iPhone is to:

1. Hold the top button down until it says "Slide to Power Off" on the screen.

2. Slide to power off.

3. Press top button again to turn back on.

Nothing is working for my 4S. Resetting network settings, renewing leases, restarting, turning off SIRI. Nothing.