I just downloaded the 4.0.2 software update and was in the process of installing it on the iphone 4 when about 50% of the way through it just frezzes. About 2 hours had gone by with no progress so I decide to disconnect the phone from the usb. The phone was then stuck on the apple logo so I tried a complete system restore. Once again the restore gets about 50% of the way through and is now stuck on the "Restoreing iPhone software" part. What should I do?