Last month I buy this Iphone 4 and because of the internal problem I try to perform an upgrade task on it. I upgrade this iphone to the IOS 4.3.1 and it shows successful message. But after that when I trying to press the Home button, then it donít work well. I donít know why this happen on this iphone. I need the special kind of solution that can be help to remove this problem on that iphone. Thanks for any kind of help.