iPhone 3GS iOS 4.2.1 JB BB 5.13.04 unlocked

So after a few more hours of reading, and some faith that I wouldn't trash my newly Jailbroken (JB) iPhone 3GS...I dove into the iOS 4.2.1 upgrade...

In our previous episode we noted that since I had Baseband (BB) 5.13.04 (which is easily unlockable with ultrasn0w) I should try to keep it.

iOS 4.2.1 is Jailbreakable...so I could simply install it and JB it...

But if I upgrade to 4.2.1, using iTunes the BB will also be upgraded...and if the BB is upgraded, I can't easily unlock it.

So I need to be able to upgrade the iOS without changing the BB.

Enter sn0wbreeze.

There are a couple of tutorials out there, they show what is happening...but leave out some important info.

First, download the normal iOS 4.2.1, plenty of websites have the link for it.

Second, download the current version of sn0wbreeze (2.2.1 is what I used)

So now we run sn0wbreeze (as administrator), click a couple of OKs and load the 4.2.1 .ipsw you got from the internets.

-The program will say it is a valid ipsw. (or you need to download a different file)

-Next menu give you a choice of simply preserve baseband, simple, or expert.

-Believe it or not, we want 'Expert'.

-In the Expert menu, there is really only one thing to select, and that is the 'General' submenu.

--In this menu, you may not need to do anything, depending on how you use your phone.

---If you will continue to use AT&T for your phone service, then UNCHECK where it says 'Hacktivate' on the right column.

---If you will NOT use AT&T, ie. you plan on unlocking later, then CHECK the 'Hactivate'

--That is the only thing you need to do on that menu, select next, and next.

-Now back in that Expert menu, at the bottom you can select create ipsw (or however it is titled...the box at the bottom of the menus).

This takes about 10 minutes or so for it to create a new ipsw.

Now the sn0wbreeze software walks you through putting the phone into recovery mode, make sure it is plugged into your computer before you start.

-it will tell you the phone is ready and for you to start iTunes, and SHIFT select 'Recover' when iTunes gives you the prompt.

It will chug away, and after another 10 minutes or so, the phone will reboot and appear, taa daa.

I had no errors, and no do overs...it worked correctly the first time.

I don't recommend restoring the iPhone from backup at this stage...treat it as a new phone.

I did all that, and when I synced my apps...the ones that need 4.2 to run suddenly appeared on the iPhone.


Whew, no bricks!