Iphone 3 GS Update Help Needed

[drsamirkhan]

Hello friends i have Iphone 3Gs with ios 4.1 which is jailbreaked & unlocked with ultrasnow, BB 6.15.00
now i want to update to latest ios 6.1.3 But my iphone is not factory unlocked & i dont know its official carrier
so please guide me to update it to 6.1.3 step by step without getting it locked. thank you.

 

[willerz2]

Your device is currently unlocked using UltraSn0w. UltraSn0w has no support above iOS 6.1, so if you upgrade your iOS to 6.1.3, you cannot use UltraSn0w to jailbreak, meaning you have to get an IMEI unlock or carrier unlock. You can narrow down the list of possible carriers by comparing the phone's model and region. If you're not the original owner of the device, you can't get a carrier unlock and your only option is an IMEI unlock.

If you have iOS 6.0-6.1 blobs manually saved (not through Cydia), you can selectively restore to that iOS that you have blobs saved for and keep it unlocked using UltraSn0w by preserving the baseband.

If you can't or don't want to get an IMEI unlock, or you don't have a usable iOS 6.0-6.1 blob saved for your specific device, then upgrading to 6.1.3 will result in a locked device.