For some reason my iPhone has been going nuts lately. It seems that anytime I reboot it, turn airplane mode on/off, or simply change location by driving a few miles, I lose my 3G data connection.
The most obvious symptom is when I launch Safari, which tells me it cannot open the page and displays this error message: Safari cannot open the page because it is not connected to the Internet.
The fix is pretty obvious and I’ve known about it for a while, but for some reason I didn’t think about applying it.
To stop this, simply go to Settings > General > Reset > Reset Network Settings. Your iPhone will reboot and you should now be able to connect to the Internet via 3G.
If you have a similar issue, I hope this quick and simple fix will do the trick for you.