If your iPhone 4 is Unlocked with Gevey sim running iOS 4.x and you want to update to iOS 5.0.1 firmware with Gevey Unlock, follow this step by step guide .
You must first preserve your iPhone 4 baseband that can be unlocked with Gevey SIM.
Fitst you must restore your iPhone 4 with custom iOS 5.0.1 ipsw with Redsn0w 0.9.10b5 to preserve your baseband.
Gevey SIM iOS 5.0.1 Supported Basebands
Gevey Sim can unlocks this iPhone 4 basebands: 01.59.00 / 02.10.04 / 03.10.01 and 04.10.01
To Unlock iPhone 4 iOS 5.0.1 You Must To Download:
- Download Redsn0w 0.9.10b5
- Download iOS 5.0.1 ipsw iPhone 4
- Download iTunes 10.5.3 for Windows and Mac
Steps to Unlock iPhone 4 on iOS 5 with Gevey SIM
Step 1: Connect your idevice with your PC via USB and open Redsn0w.
Step 2: Select Extras and then select Custom IPSW option so that you can create your pre-jailbroken custom firmware for your iPhone
How to Permanently Unlock iPhone 4
Step 4a:You must put your iPhone in DFU Mode. Just follow the onscreen instructions to put your iPhone in the DFU Mode.
Step 5: If your iPhone is in DFU Mode open iTunes and restore with the Custom iOS 5 ipsw (Customized ispw file name begins with NO_BB).