How to Downgrade iPhone 4S on iOS 5.1 / iOS 5.1.1 to iOS 5.0.1 Using Redsn0w

While we wait for pod2g to release his untethered jailbreak for iOS 5.1.1 for iPhone, iPad and iPod touch, Dev team has released a new version of Redsn0w (0.9.11b1) that allows iPhone 4S and iPad 2 users to downgrade their iOS device to iOS 5.0.1 so that they can use the Absinthe jailbreak to jailbreak their device.

This is a step-by-step guide for users to downgrade their iPhone 4S on iOS 5.1 or iOS 5.1.1 to iOS 5.0.1.

Some important points before we proceed:

This guide is meant for iPhone 4S users, we will publish a guide for iPad 2 users shortly.This method will work only if you've saved your SHSH blobs for iOS 5.0.1 either using TinyUmbrella or had jailbroken your iPhone when it was running iOS 5.0.1 and launched Cydia at least once, which would have cached the SHSH blobs on its servers.This method first updates iPhone 4S to the latest firmware and then downgrades it to iOS 5.0.1, so in the process it updates iPhone's baseband. If you depend on Ultrasn0w then you should avoid using this method to downgrade.Since the method restores your iPhone with iOS 5.0.1, you need to go through the process of setting up your iPhone from the backup, which will take sometime.Please also make sure you've taken a backup of your iPhone either to iCloud or to iTunes.Here's the step-by-step instructions to downgrade your iPhone 4S using Redsn0w:Step 1: Download Redsn0w for Windows from this link and Redsn0w for Mac from this link and save the application in a folder named "Redsn0w" on your desktop.Step 2: Download iOS 5.1.1 firmware file and iOS 5.0.1 firmware file for iPhone 4S.iOS 5.0.1: iPhone4,1_5.0.1_9A405_Restore.ipswiOS 5.1.1: iPhone4,1_5.1.1_9B206_Restore.ipswPlease note both the firmware files are required for the downgrade process. If you're downloading the firmware files using Safari then ensure that auto unzip feature is disable or use Safari or Chrome to download the firmware files.Step 3: Please turn off your iPhone and connect it your computer.

Step 4: You will now need to put your iPhone into the DFU mode. You can follow these simple steps to put your iPhone in DFU mode:

(a) Hold the Power button on iPhone down for 3 seconds:

(b) Now simultaneously hold the Home button and keep the two buttons pressed for 10 seconds:

(c) Now release the Power button while keeping the Home button pressed until your iPhone's screen goes black or iTunes pops up a message telling you that it has detected an iPhone in recovery mode.

Step 5: Double click the Redsn0w zip file and extract the application to the Redsn0w folder. Navigate back to the Redsn0w folder and launch the Redsn0w application. Please ensure that you have launched the latest version of Redsn0w (0.9.11b1).

Windows 7 users should run the exe in Windows XP compatibility mode (right-click on the Redsn0w exe and select Properties, then select the Compatibility tab and select Run this program in compatibility mode for Windows XP). Windows XP and Windows 7 users should run Redsn0w as 

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