How to unlock iPhone for T mobile—or any other carrier, for that matter!—can be simple or impossible. In GSM phones, unlocking, unlike jailbreaking, is not blocked by the device’s encryption code. Rather, the service provider, such as T-Mobile has programmed the firmware to recognize only a specific brand of SIM. The iPhone’s firmware has an option to unlock the device when a certain number is entered based on the International Mobile Equipment Identity (IMEI). This number can be typically generated only by the carrier network. How to unlock iPhone for T mobile without this number is possible. But unfortunately it will not work for all iPhones. You can try a software unlock such as ultrasn0w.
How to unlock iPhone for T mobile using ultrasn0w requires that you jailbreak your phone first. Depending on your iOS and firmware, you can use several jailbreaking software. However, since ultrasn0w is limited in terms of the baseband it can work with, you will probably need to use Sn0wbreeze for Windows or PwnageTool for Mac to preserve your baseband. Using other software that does not generate a custom IPSW will update your baseband, and this will most probably not be in the baseband requirements of ultrasn0w. How to unlock iPhone for T mobile using ultrasn0w will only work if your modem firmware is on baseband 04.26.08, 05.11.07, 05.12.01, 05.13.04, 06.15.00, or 01.59. Anything else is no good. For other basebands and iDevices, check out BestJailbreakSoftware.
As the first step on how to unlock iPhone for T mobile, find out what your modem firmware is.
If your modem firmware is not in the list, then you will probably need to find another way how to unlock iPhone for T mobile. If you’re in luck and your firmware is in the list, then be sure NOT to change your baseband by updating your iOS using stock firmware in iTunes.
This is how to unlock iPhone for T mobile using ultrasn0w!
Author: Kaye Navarro