For those iPhone users who are locked at certain networks and they unintentially upgrade to iOS 5.0.1 or iOS 5.0 through the itunes official update and get updated to baseband 04.11.08, the question that arises is whether they can downgrade their baseband back to 04.10.08 or not? Unfortunately the answer is NO, there is no such way introduced to downgrade the baseband of your iPhone from 04.11.08 to 04.10.08 up untill now, but there are certain ways that you can adopt to upgrade to iOS 5.0 & 5.0.1 (keeping the baseband preserved to 04.10.08) using this step by step procedure introduced below:
Note: This procedure is for only those users who are using iPhone 4 with Baseband 4.x.x.
Download IPSW (iPhone Software) 5.0 or 5.0.1 from the link.
Download Sn0wbreeze version 2.8 beta 11 from here which supports (IPSW 5.0.1 9A405).
For Windows Users : Download
Open Sn0wbreeze 2.8 Beta 11 and follow the pictorial instructions. This method will create another IPSW of Sn0wbreeze with your old baseband which is 04.10.08.
At First backup all your data and then launch downloaded Sn0wbreeze.
click the Blue next Button.
Now click Browse.
Now select the downloaded IPSW.
Now after selecting the downloaded IPSW, click next.
Click “Baseband Preservation Mode” & click next. (This mode will preserve the Baseband, there is no need to select Simple Mode because it tether jailbreaks, where as untethered jailbreak is available via Redsn0w)
Now it will start creating the new IPSW on the “Desktop” of your computer.
After the IPSW will be created Click “OK“.
Now follow the instructions and it will take the iPhone into DFU mode, keep the computer connected to the Internet while the iPhone is taken into DFU mode.
Once you are successfully into the DFU mode, open iTunes and hold the “Shift key” and click “Restore” and then select the IPSW created by Sn0wbreeze on the “Desktop” with file name as “sn0wbreeze_iPhone 4-5.0.1.ipsw” and now relax for some time while the iTunes restores the iPhone to iOS 5.0.1 with the firmware 04.10.08, allowing you to use Gevey with your iPhone easily.
To skip the registration process. Download Redsn0w Version 9.10 Beta 3, then Launch Redsn0w, connect the iPhone to the computer and then follow the given instructions and after a while you’ll have an Untethered Jailbroken iPhone and this time when when the iPhone will be restarted automatically, it will again ask for Online Verification but this time it will not ask for any Carrier Option and you can directly backup your iPhone Data via iCloud for iOS 5.0 users and via iTunes for iOS 4.x.x Users or it can be set as a new iPhone, enjoy the Jailbroken iPhone, follow the instructions for the Gevey Sim and enjoy the unlocked Jailbroken untethered iPhone iOS 5.0.1 with Baseband 04.10.08.
Once you’re done, you’ll come up with something like this:
Note: iOS 5.0 & 5.0.1 also offers iCloud and you can set your iPhone backup directly to the iCloud over the air and to set up an iCloud account, goto Settings >iCloud >Storage & Backup > Back Up Now. Standard space is 5GB but you can buy to upgrade more space if required and backup all your data over WiFi to iCloud.