iOS 4.1 was released yesterday with new features as well as annoyances for jailbreakers and unlockers. It updates the baseband on your iPhone 4 to version 2.10.4 which so far isn’t unlockable, which means you can’t use ultrasn0w t0 unlock your iPhone 4 to work with other carriers once you update to iOS 4.1.  The best way to avoid this issue is by simply not upgrading to iOS 4.1. The other method is to preserver 159.00 baseband while upgrading your iPhone 4 to iOS 4.1.

It wasn’t possible until Notcom, the developer behind TinyUmbrella, updated it to version 4.1.3 which lets you save SHSH blobs.  It also lets you update to iOS 4.1 without upgrading the baseband. Follow our guide on how to do that:

Remember though, until there’s a jailbreak available for iOS 4.1 on iPhone 4, you wont be able to use ultrasn0w. So proceed with caution and backup your SHSH blobs first. We’re not responsible for any problem caused to your iPhone 4 with this guide.

iPhone 4 iOS 4.1 with Baseband 1.59.00

  1. Download TinyUmbrella 4.1.3
  2. Close iTunes and run TinyUmbrella
  3. Click on Save My SHSH to backup your iPhone 4 SHSH blobs.
  4. Check advanced options and in device drop down box, select iPhone 4.1 and save My SHSH again.
  5. Start TSS Server in TinyUmbrellaTinyUmbrella iPhone 4 Start TTS
  6. Now open up iTunes and upgrade to iOS 4.1. You can either do that from within iTunes or download the firmware directly from here.
  7. You’ll get an iTunes error 1004. This means your baseband update failed.
  8. All you have to do now is kick the device out of recovery.Kick-out-of-Recovery1

That’s it. You’ve upgraded your iPhone 4 to iOS 4.1 with 1.59.00 baseband.

[via BlogsDNA and Apple Press]