Here is a guide on how to use Gevey Sim on iOS 5.1.1 iPhone 4 and enjoy your unlocking iPhone. You ca use it after updating your iOS to 5.1.1 and preserving old baseband.
A few hours ago I wrote you a guide on how to preserve iPhone old baseband updating to iOS 5.1.1. It is very important when you want to keep your unlocking baseband alive. I think that you know when you updating your iOS through iTunes it automatically updates your baseband too. So don’t do this, first you need to preserve old baseband.
I’ve already shown you how to preserve iPhone 4 and 3GS baseband. And now I’ll show you how to unlock iPhone 4 after update.
If you are iPhone 3GS user you can try to use Ultrasn0w 1.2.7 for unlock, And if you are iPhone 4 user you can try Gevey Sim on iOS 5.1.1 for iPhone 4 unlock and I’ll show you how to use it. But first take a look which basebands are supported by Gevey Sim.

Supported basebands

  • 02.10.01
  • 03.10.01
  • 04.10.01

How to Use Gevey Sim on iOS 5.1.1 iPhone 4

Step 1. After successful restoring you need to eject your Sim and reboot iPhone.
Step 2. After rebooting go to Settings => General => Network and turn off 3G and Cellular data.
Step 3. Take your Sim card and insert it with Gevey Sim in iPhone 4.
Step 4. When Accept screen appears tap Accept.
Step 5. After accepting you will see No Service. Don’t worry and wait for 15-20 seconds and dial 112, wait for 1-2 seconds and hang up.
Step 6. Now you need to turn on Airplay mode and till message No Sim Card Installed pops up and turn Airplay mode off. Now you must see Sim Failure so tap OK and your iPhone should connect to your network.
If everything is find and your iPhone is connected to your network you can enjoy your phone calls. Now you can use Gevey Sim on iOS 5.1.1 iPhone 4 without problems. But if there are some that use comment sections below.
If you are iPhone 4s user you can buy Gevey Ultra S for CDMA 4S on basebands up to 04.10.01 and unlock your phone too.