The following are instructions on how to update your iPhone 4 or 3GS to 4.3.3 while preserving the baseband. For your convenience i have included ready-made custom IPSWs which don’t update the baseband. Open up the full link for the whole guide.

NOTE – Apple has stopped signing 4.3.3 Today so be sure to follow the guide HERE before continuing with this one.
NOTE – For those facing issues with MMS or Facetime, follow the guide HERE to fix it.
Tools you’ll need:
iPhone 3GS Â 4.3.3 Custom IPSW . Click here.
iPhone 4 4.3.3 Custom IPSW . Click here.
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iPhone 3GS 4.3.3 Official.  Click here.
iPhone 4 4.3.3 Official. Click here.
Redsn0w 0.9.6 rc16. Click here.
TinyUmbrella. Click here.
An iPhone 3GS Â with Baseband 05.13.04 or Below.
An iPhone 4 with Baseband 01.59.00 or Below.
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Step One
Download iPhone 3GS/4 custom and official IPSW. Download and extract Redsn0w. For convenience, place all of them in a folder on the desktop, like so:

Step Two
Open up Redsnow. If you are on Windows 7, you will have to run Redsn0w as an administrator and in Windows XP SP3 Compatibility mode. Click browse.
Step Three
A window will appear, point it towards the Official IPSW for your phone which we previously placed in the folder on the desktop.
Step Four
Once the IPSW gets verified, click the Next button. Redsn0w will then prepare the jailbreak files. Â You will then be shown a menu with many options. Untick all except for “Just Enter Pwned DFU mode Right Now” and click Next.

Step Five
Connect the iPhone to the PC and then proceed to switch it off. Once the phone is fully turned off click Next. Remember to hold the phone in your hand before you press next as you will have to press various buttons on the phone to make it  enter DFU mode.
Step Six
After pressing next, instructions to enter DFU mode will appear. To enter DFU mode, hold the power button for 3 seconds, then without letting go of the power button press the home button and power button together for 10 seconds after which let go of the power button and continue to hold the home button until your PC detects the phone. It may take several tries to get into DFU mode.

Once the phone has entered DFU mode, the process will begin. The phone will reboot.

When it’s completed it will show you this message. Now your device is ready to accept custom IPSWs from iTunes.
Step Seven
Launch TinyUmbrella and press the “Start TSS Server” button. Keep TinyUmbrella running.
Fire up iTunes and it will instantly show you the following message.
Press OK.
Step Eight
On the iPhone menu in iTunes, hold shift and press the restore button.
Step Nine
iTunes will now ask you to locate the IPSW file. Point it towards the Custom IPSW that you downloaded and placed in the Jailbreak folder.

iTunes will then restore your iPhone with the custom firmware. This process will take about ten minutes and iTunes will notify you once the process is complete. The phone will then restart.
After the reboot the phone will be Jailbroken and activated on 4.3.3 with cydia on the homescreen. If the phone fails to activate or Cydia isnt working(very unlikely) continue onto the next steps.
Step NineÂ
Open up Redsn0w again. Click browse and select the Official IPSW file (Refer to step 2 and 3). Click next. This time around, select only “Install Cydia” and leave all other options unticked.

Step Ten
Click Next and then connect the iPhone and turn it off. After it has fully shut down, Click Next (Refer to step 5 and 6). Follow the on-screen instructions and after you have successfully entered DFU mode, the process will begin.


It will notify you when it’s complete. The rest of the process takes place on your phone (This usually takes around 5 minutes). If all has gone well you’ll see a running pineapple logo on your screen. Your phone will reboot after that is completed and then you’ll have and activated and jailbroken phone with the baseband left untouched. The Cydia icon will be on the springboard.
The end result is that we will have the iPhone on 4.3.3 but the baseband will be whatever you started from(05.13.04) in this case as opposed to the 05.16.02 on the stock firmware. Now you can simply go to Cydia and install Ultrasn0w and your phone will be unlocked. And that’s it.
Feel free to leave any suggestions or queries in the comments below.
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