When you attempt to restore a custom IPSW created by tools like or PwnageTool , iTunes often blocks the process because the firmware is unsigned or modified. iREB works by putting the device into a "Pwned DFU" state. It achieves this by uploading three specific patched files to the device’s memory, which "tricks" iTunes into accepting the custom firmware without triggering 16xx-series errors. Using iREB 4.0.x 4.1 RC2 To use this tool effectively, follow these general steps:

The Release Candidate 2 (RC2) version brought several updates to the tool's stability and functionality:

Review and Tutorial on how to get and use iREB and f0recast.

: Connect your device to your computer and put it into standard DFU mode manually.

This specific release supports a wide range of legacy hardware, including: : 2G, 3G, 3GS (both old and new BootROM), and iPhone 4. iPod Touch : 1G, 2G (MB and MC models), 3G, and 4G. : 1st Generation. : 2nd Generation. General Usage Steps Preparation : Download the iREB 4.0.x 4.1 RC2.zip and extract its contents to your desktop. Enter DFU Mode