Got 3GS 4.1 16.15.00 new boot - How high can I upgrade

[Banderaz69]

Hi,
Got a 3gs, with 06.15.00, new boot room, and I must unlock aswell.
It is jb and unlocked today, but want to upgrade to a higher firmware. Too much apps that is not possible for me to use

So, how high can I upgrade, preserving unlock, jb and unthethered?

Thank you for all help. (Read the great tutorial about old bootrom and 5.1.1, but found out that I have new...)

Edit: My phone is from 2009, week 45.

[123hiten]

If u have 06.15.00 its iPad base band and if u want to go to 5.1.1 u can make custom firmware with red snow and update ur iPhone without doing anything to baseband 06.15.00 this may work or u mute get error while updating custom firmware on itunes


Option two
Download 5.1.1 on our computer from some website like redmontpie etc update ur phone with 5.1.1 once updated go to jailbreak process while jail breaking the iPhone select option install iPad base band complete the process start the phone after JB go to cydia install ultrasnow reboot now u shud have jailbreak as well as unlock
Hope this helps let me know if any thing else u want

[tehh4ck3r]

To upgrade:

Download the latest version if iTunes and the iOS 5.1.1 firmware for the 3GS
Download the latest version of redsn0w- http://blog.iphone-dev.org/post/2653...seband-freedom
Create a NO_BB ("no baseband") custom IPSW using redsn0w- open redsn0w, click "Extras", and click "Custom IPSW"
Enter pwned DFU mode- In redsn0w, go back to the Extras menu and click "Pwned DFU".
Open iTunes and hold down the "Shift" key (on Windows) or "Option" key (on Mac) and click on Restore.
Navigate to your custom IPSW (the NO_BB ipsw) and select it.
Then continue with the restore as normal.

Afterwards you can use redsn0w to jailbreak and downgrade your BB if you want.

[Banderaz69]

Thank you for good answers
And after your guide, tehh3ck3r, will I be able to unlock?

[tehh4ck3r]

Yes, you can either unlock on baseband 6.15.00 or downgrade using redsn0w and then unlock.

[defender487]

big thank you to techhacker thanks again