3gs upgrade

[jimjoekim]

Hi all,
new to this site, looks great,
question ....
i have 3gs new boot rom firmware 4.0.1 jailbroken and unlocked, can i upgrade the firmware , do i need to preserve the baseband and what firmware should i upgrade too ?

Thanks for any help

[Orby]

Hi all,
new to this site, looks great,
question ....
i have 3gs new boot rom firmware 4.0.1 jailbroken and unlocked, can i upgrade the firmware , do i need to preserve the baseband and what firmware should i upgrade too ?

Thanks for any help

In order:
Yes, you can upgrade the firmware.
Yes, you should preserve your baseband (if you rely on ultrasn0w for your unlock). You can do this via the current version of redsn0w (0.9.15b3, download for Windows or OS X here), using Extras -> Custom IPSW.
The only firmware you can upgrade to at this time is iOS 6.0.1 (unless you have SHSH blobs saved for prior firmwares... if you see any green numbers at the top of your Cydia homepage, then those are the versions of iOS you can restore to).
Example:

[jimjoekim]

ok, i have upgraded to 5.1.1using redsnow, preserving baseband, but i cannot restore on itunes as it says sim is invalid, the phone is totally wiped and i am just stuck with the iphone set up as if it is a totally new phone but with nothing on it , ie no apps !

Help please