Andreas Dolinsek's Weblog

Many developers have to support the old 2.2.1 firmware for their applications. Here is a short and easy guide HowTo do the downgrade from 3.0 back to 2.2.1:

For the guys who had problems like: error 20, 1600, 1601, etc.

Software needed:

• iTunes 8.2
• QuickPwnRC3
• iPhone Firmware 2.0.2 (ipsw) for your iPhone/iPod Generation
• QuickPwn 2.2.5 (for Firmware 2.2.1)

Steps for downgrade:

1. Open QuickpwnRC3 and follw the steps and select 2.0.2 IPSW
2. when your iPhone screen turns to complete white color , unplug the USB – your iPhone will remain with the white screen in recovery mode
3. Exit QuickPWNRc3
4. Reconnect iPhone
5. iTunes will discover iPhone in recovery mode.
6. E-Shift+Restore to 2.2.1 (with Quickpwn 2.2.5)

happy testing!