Apple released their latest iOS4 firmware for the iPhone 3G, 3GS, & iPod(s). It’s an exciting time for everyone since there are tons of new features in this new firmware. The iPhone Dev Team was quick to release new tools to enable you to unlock your iPhones with great ease. I’ve just finished successfully jail-breaking & unlocking my iPhone 3G and have thus decided to show you folks how to do it.
REQUIREMENTS:
iPhone 3G *WARNING* DO NOT FOLLOW THIS GUIDE IF YOU OWN AN IPHONE 3GS*
Wi-Fi Connection [only for ultrasn0w installation]
USB Cable to connect your iPhone to your PC/Mac
Latest version of iTunes
Windows or Mac OS X
Step 1:
Download the iOS4 firmware along-with the redsn0w that corresponds to your OS.
iOS4 firmware for iPhone 3G
redsnow 0.9.5b5-3 Mac OS X
redsnow 0.9.5b5-3 Windows
Alternatively, iTunes will ask you now when you connect your iPhone 3G and you can simply click on “Download & Install” and your iPhone will be updated to the latest firmware. Just make sure that it’s iOS 4.0 and not something that comes out a few days hence since they’re sure to patch the baseband vulnerability in the next version.
Step 2 [Optional]:
Create a back-up of your iPhone. Do this by connecting your iPhone to your PC/Mac and right clicking on your iPhone in the iTunes Side-bar and selecting Backup. Alternatively, if you don’t want a back-up, you can run the following command in a terminal window [Mac OS X] and this will prevent the iPhone from creating a backup during the update/restore process. This is good for those people that don’t want a backup since the iPhone takes AGES to create a backup.
defaults write com.apple.iTunes DeviceBackupsDisabled -bool true
Step 3:
Restore your iPhone 3G to the latest firmware by holding down the Option Key (Mac Users) or the Shift key (Windows) and clicking on Restore in your iPhone Options screen within iTunes. Choose the firmware you just downloaded so that iTunes restores your iPhone 3G to the new firmware.
If you want to keep your apps & settings, choose to update it rather than restore. Again, hold down the Option key to select the correct IPSW or allow iTunes to update the iPhone automatically.
Step 4:
Once your iPhone 3G has rebooted and now has the new firmware you will be locked in if you don’t have an official carrier’s sim and your iPhone isn’t factory unlocked. Now is the time to use redsn0w to jailbreak this bitch!
NOTE: DO NOT PANIC IF YOUR IPHONE REBOOTS INTO RECOVERY MODE. THIS IS NORMAL.
Run redsn0w for your OS.
Browse for the IPSW that you just restored your phone to. If you asked iTunes to automatically update your firmware will be located in:
~/Library/iTunes/iPhone Software Updates
Select the 4.0 firmware IPSW.
[Hint: it's called iPhone1,2_4.0_8A293_Restore.ipsw]
Then, redsn0w will tell you that the IPSW has been identified. Now click Next. After a short while, it’ll show you some options.
Choose the options that you like. [for those that need an unlock, make sure you install Cydia]
Click Next.
Follow the instructions on entering recovery mode. They’re very easy to follow, just do it! :)
redsn0w will start jailbreaking your phone. Be patient while it does so. This may take upto 10 minutes. (more if you’re on USB 1.1)
Step 5:
Once the jailbreak is complete, your iPhone will reboot with iOS4. Since redsn0w has already activated your phone you can stop here if you don’t need a carrier unlock.
Only follow Step 6 if you DO need a carrier unlock.
Step 6:
Now with your new OS on your phone, make sure you’re connected to your Wi-Fi network and then load Cydia. Cydia will need to reload and update it’s data in some cases, let it do so. [this might take a while depending on your internet connection speed...]
Cydia might exit and return to the springboard. In this case, simply restart Cydia, again wait for it to download packages and update all the necessary info it needs. If it asks you to upgrade essential or do a complete upgrade go for the Complete Upgrade. [always better..]
Next, go to Manage -> Sources -> Edit ->Add.
Add this URL exactly as it is:
http://repo666.ultrasn0w.com
[That's a ZERO between sn0w and not an O..]
Select Add. Once the repository is added, Cydia will automatically load ultrasn0w into it’s package database. You still need to INSTALL it however. Go to Search. Type in “Ultra”. Hit Search. You’ll find ultrasn0w. Select Install -> Confirm. Once the installation is complete, the iPhone will reboot.
Step 7:
Once your iPhone 3G reboots, you should see your carrier appear at the top of the screen. All done! Now if you want to restore your applications and their data, sync with iTunes and restore your backup after that. This will restore your contacts, applications, and other data. Cydia apps will need to be re-installed.
Congratulations! You’ve successfully updated your iPhone 3G to the latest iOS 4.0. There are tons of new features and noticeable speed improvements right off the bat!
Questions and comments are welcome :)



