How to upgrade 3g from 3.1.2 to 4.0.1

[VeganBeauty]

How to upgrade my jailbroken and unlocked iPhone 3g from 3.1.2 to 4.0.1?

[iYeow]

First download tiny umbrella , plug iphone in and click save shsh

[VeganBeauty]

Thanks. Do I find tiny umbrella in Cydia?

Ok. I found out where to get tiny umbrella, but it doesn't seem like it's being downloaded to my PC. Any suggestions.

[iYeow]

HERE : The Firmware Umbrella - TinyUmbrella

[VeganBeauty]

Thanks. I did exactly as you suggested and downloaded tiny umbrella, plugged in my iPhone and clicked save shsh. Now, what should I do next?

[iYeow]

What shsh do you see ?

[VeganBeauty]

iPhone3G 4.0 (8A293)
iPhone3G 4.0.1 (8A306)
iPhone3G 4.0.2 (8A400)
iPhone3G 4.1 (8B117)
iPhone3G 4.2.1 (8C148)
iPhone3G 4.2b3 (8C5115c)

[iYeow]

Good, Now you can go and build a custom firmware of 4.1 from Pwnage tools 4.1.2 or Snowbreeze 2.1
Use either Pwnage tools or redsn0w 0.9.6b6 to put you into dfu mode and the run itunes : shift/alt/option + restore ( itunes) to custom fw of 4.1
It will preserve your bb of 05.11.07 this way to be unlock with ultrasn0w.

Your current baseband can be unlocked, so don't use ipad baseband.

When you run redsn0w, you browse to stock 4.1 fw and only check the box : DFU mode only.

[VeganBeauty]

Where do I browse to stock 4.1 fw and only check the box : DFU mode only? Browse to my iPhone or on my PC?

[iYeow]

When you run redsn0w, it will ask for firmware, you will browse to stock fw otherwise you cannot proceed any further and is done on a pc or mac

[VeganBeauty]

Thanks. I see. I am getting the following message: "Unable to recognize specified IPSW."

I went to iClarified - iPhone - Where To Download iPhone Firmware Files From and downloaded the 4.0.1 (3G): iPhone1,2_4.0.1_8A306_Restore.ipsw. Is this correct?

[iYeow]

You point to 4.1 fw.

[VeganBeauty]

Ok. That worked. Are there any particular options I should/need to select on the next screen?

I ran redsn0w and browsed to stock 4.1 fw and only checked the box for DFU mode. What should I do next?

[i.Annie]

Then you'd find or create a custom 4.1 ipsw and shift+restore to it in iTunes. You can create one with Sn0wbreeze 2.0.2 (I don't recommend 2.1 for the 3G) or find one online made by PwnageTool. I think PwnageTool is more stable, but if you don't have a Mac you can't make it yourself and you'll have to Google it (or ask someone who has one to send to you).

[VeganBeauty]

Thanks. I did as you suggested and my iPhone is currently on ios 4.1. It is unlocked and jailbroken too!! My only issue now is that I can't seem to get my phone back on T-mobile. I've tried so many times, but it keeps saying "Searching..." instead of T-mobile as my carrier. Do you have any suggestions or can you point me in the right direction, so I can make calls again on my phone?

[iYeow]

Go check your baseband in general > about

And your carrier too

[VeganBeauty]

Carrier = Carrier 8.0

I don't see baseband details

Modem Firmware = 05.14.02

[i.Annie]

That baseband is not unlockable.

[VeganBeauty]

you need to upgrade to 06.15 in order to unlock it

Thank you! How do I upgrade to 06.15?

[VeganBeauty]

I have an iPhone not an iPad. What should I use for an iPhone?