The iPhone is one of the most popular and powerful products ever released. Since its original release in 2007, the iPhone has revolutionised the smart phone industry. The iPhone has such a devoted following that whenever a new version is released, people line up for hours in front of Apple stores around the country.
The popularity of the iPhone does not mean that the product is without faults. Many users have felt the frustration of being stuck with a frozen and therefore useless phone. In these cases sometimes the built-in reset trick of holding the Sleep/Wake button and the Home button simultaneously will prove unsuccessful. Usually the issue can be resolved with a simple paper clip.
Look for a tiny hole that is located between the hold button and the headphone jack on the original, 3G and 3GS iPhone models. On the newer iPhone 4 this hole is located on the right side of the phone.
Unfold a paper clip and gently push the pointed end into the hole. This will cause the SIM card tray to pop up. Push the tray back into place until it is back in the original position.
Wait approximately 1 minute. After the wait you should notice that the phone has been reset and your signal display will return to normal.