Ming Wireless

After your unlocking Or Jailbreak your iphone on 3.1.2 Firmware might get the problem for your iphone can not cennected to Wi-Fi.

NOTE: Your iPhone 3G/3GS should be fully unlocked by using blackra1n RC3 & blacksn0w.  for complete instructions on jailbreaking your iPhone with blackra1n RC3 and instructions on blacksn0w.

FIX-1: Reset Network Settings of your iPhone

As per GeoHot, he received enormous WiFi/Hotspot connection issues/queries from users who upgraded their iPhone using blacksn0w/blackra1n RC3. The resolution he recommended was to reset your network settings of your iPhone. Follow following simple steps to reset your iPhone's network settings.

Step-1: On your iPhone, go to Settings –> General –> Reset –> Reset Network Settings. You will see a "Reset Network Settings" button as shown below.

Step-2: That's it. Just touch this button and give a power cycle to your iPhone, i-e turn OFF and then turn ON your iPhone.

Please keep in mind that this isn't a permanent solution to this WiFi bug, it may arise again and you may have to perform same steps to reset settings again.