Solve iPhone Error 1600 on 2G – Jailbreak Custom Firmware 3.1

The 1600 error in iTunes is caused by already upgrading to 3.1 firmware. If you do this and then try to upgrade to a custom 3.1 firmware. iTunes knows that it has been modified and will not let you install. Luckly you can delete this file and install your custom firmware without the 1600 error.

Instructions

Delete Old Data

• Navigate to the following folder on XP

C:\Documents and Settings\%username%\Application Data\Apple Computer\iTunes\Device Support

• or on Vista/7

C:/users/%Username%/AppData/Roaming/Apple Computer/iTunesDevice Support/

• Inside there will be a file called x12220000_5_Recovery.ispw. Backup this file and delete the original.

• Now copy and paste your custom firmware into this folder and rename it so it is the same as the one your backed up/deleted

Delete Original Firmware

• Now navigate to the following folder

C:\Documents and Settings\%username%\Application Data\Apple Computer\iTunes\iPhone Software Updates

• Delete the files in here (Backup if you wish)
• Now copy and paste your custom firmware and change it to the correct apple name. Which should be

iPhone1_1_3.1_7C144_Restore.ipsw

Restore

• Now put your iPhone into DFU mode and Shift+Restore and usual