Why can't my iPhone 4s restore?
Recently I have replaced my Iphone 4s screen and everything worked perfectly fine right after I had assembled it. After about 2 hours, my iphone 4s turned off twice. The first time, I started it back up and it worked. The second time, I was hopeless and the screen would not start back up. Later, I tried to connect it to Itunes and it can't restore because of error 21. I've tried literally everything (redsnow extras, modify hosts file, ipsw file, replacing battery, and DFU mode). Can someone help me resolve this problem?