How to Update Your iPhone 4 Without Upgrading the Baseband (Mac)

Does this procedure still work? I've got JB iPhone 4 @ 5.1.1, but locked w/ modem fw 4.12.01, so I'm looking to first downgrade to ipsw with unlockable modem fw, then upgrade, preserving unlockable modem fw. Thanks for any advice.

I cant update my iphone4 4.0.1 to 4.1 using tinyumbrella 4.1.13. Ive tired several computers mac and win7 and xp. on mac I have leopard itunes 10.0 and i start up tss server then itunes hold shift restore click iphone3_1 4.1 restore it looks like its going good it gets by the veification and preparation and starts the restore and gets stuck after 1 minute. on xp itunes 10.1 it gets stuck on preparing iphone for restore and errors out. win7 cant even contact apple server

So, I upgraded to 4.1 using PwnageTool. I am still on baseband 01.59.00 so unlock is possible. But the PwnageTool jailbreak sucks, no cellular data, no facetime. I want to redo the jailbreak using laimra1n instead. So my question is: Is it possible to do the same steps on iOS 4.1 with baseband 01.59.00 and preserving the baseband, doing a restore and jailbreaking with limera1in, without losing the ability to unlock? I would appreciate your responses on this very much. Don't want to get my phone stuck with new baseband so I couldn't unlock :P

So long as you do NOT restore via iTunes and use TinyUmbrella (and make sure the TSS Server is ON; it won't hurt anything if you leave it on) you'll be a'ight as far as the baseband goes. and yes, you can re-do it as often as you like. That said, I'm not so sure that the Pwnage Tool is bad. I think we would have heard a lot of people complain or did I miss something? Limera1n certainly works perfectly. It even asks you if you want to re-do it if you mess up. It's pretty awesome. I'd really LOVE to see a way to hack into the 2nd gen. Apple TV and get maybe Boxee on there so I can stream my 1080p's to my HDTV. :D If I'm not mistaken, the "720p 30fps" limit is only for when you use iTunes, like a good boy would. lol...

Does this work if your iPhone 4 needs to be hacktivated? I don't have an AT&T SIM.

I have done all the step with ALT + RESTORE and SHIFT + RESTORE. In both operations, it is stuck on VALIDATING SAVED SHSH... I have iPhone 4 4.1 and I have saved my SHSH... Please Help Thanks

Well, as I said in a reply to someone towards the beginning of the thread, there is one error in the instructions, one omission and they are somewhat incomplete. The error is where it says "Open iTunes and then Hit Shift and Restore". It should read "Open iTunes and Hit Alt(a.k.a. the Option key) and click on Restore without letting go" I see that a bunch of people were surprised that this basically removed their Jailbreak from their iPhone's, so maybe that should be added as the last step. There is no reason to be all up in arms about it, though. Just re-jailbreak with Limera1n after you successfully upgrade to iOS 4.1 while keeping your modem firmware (baseband) intact at 01.59.00. In my case, it finally said "iPhone activated" but it wiped everything out except what's in the iOS 4.1 software bundle. I checked if it worked, and sure enough, it was on iOS 4.1 with the baseband at 01.59.00. I then did a Restore in iTunes when it asked me if I wanted to set up as a new phone or restore from my last iPhone (backup, I guess), so I clicked on the latter. Sure enough, it copied everything back to my iPhone (apps, songs, settings, etc.) which took a while. Finally, I re-jailbroke with limera1n and here I am, on iOS 4.1 w/ baseband 01.59.00 and jailbroken + all my Cydia stuff back! :) IMPORTANT NOTE: You should leave TINYUMBRELLA AND THE TSS SERVER *ON* DURING THIS LAST RESTORE!

If you did this tutorial right, all you have to do now is use limerain to jailbreak then unlock with ultrasn0w as long as you still have the firmware 1.59. Worked fine for me!

The restore process is stuck at "Validating saved SHSH" and nothing happens. What am I doing wrong?

OK you should use the old tinyumbrella, because then it worked. The new version with the new interface seems to have a bug.

Followed the directions to a tee. When I click "Kick Device Out of Recovery", nothing happens. Now my phone is stuck in recovery mode. The out way out seems to be to click "Restore" in iTunes, but if i do that, then I lose my baseband. Anyone have any suggestions?

As the instructions state, if you're having problems at this particular point, quit TinyUmbrella and restart it. You also have to restart the TSS Server again, of course. I had the same issue as you did at this step, but restarting did do the trick. The instructions do have at least one error and are incomplete, however, see my reply to the entire thread below. Crunch

Step Five should read "Open iTunes and Hit Alt/Option key + Restore"