iOS 5.0.1 final public release hit a few hours ago and hackers have updated the jailbreak tools as well.
If you have already updated to the iOS 5.0 or 5.0.1 without preservation of the baseband then this solution cannot help.
check in about page and if you have a baseband of 04.10.08 then this will not work for you.
How to create a preserved baseband file for iOS 5.0.1 using Sn0wbreeze 2.8b11
1. iOS 5.0.1 firmware IPSW for iPhone4 Download Firmware
2. Now Download iTunes 10.5 for Windows or Mac
Apple, ahead of iOS and iCloud launch has released iTunes 10.5 final version to the public. iOS 5 and iCloud will be released tomorrow or somewhere this week as promised by Apple.
Remember, you need iTunes 10.5 to update your device to iOS 5 and enjoy all the iOS 5 features as well as the iCloud. Wi-Fi Syncing is finally here, and you’ll be able to Sync your device over the air without connecting your device. So download iTunes 10.5 today and get yourself ready for iOS 5.
Here is what you get with iTunes 10.5:
What’s new in iTunes 10.5
- iTunes in the Cloud. iTunes now stores your music and TV purchases in iCloud and makes them available on your devices anywhere, any time, at no additional cost.
- Automatic Downloads. Purchase music from any device or computer and automatically download a copy to your PC and iOS devices.
- Download Previous Purchases. Download your past music, TV, app, and book purchases again, at no additional cost. Previous purchases may be unavailable if they are no longer on the iTunes Store.
- Sync with your iPhone, iPad, or iPod touch with iOS 5.
- Wi-Fi Syncing. Automatically sync your iPhone, iPad, or iPod touch with iTunes any time they’re both on the same Wi-Fi network.
Download iTunes 10.5 for Windows
4. Run Sn0wbreeze, give it the iOS 5.0.1 .IPSW file
5. From the settings choose wisely the stuff you need. Go to Expert Mode for “preserve your baseband” option if you are a rebel micro sim user.
6. Wait for Sn0wbreezed to cook the custom iOS 5.0.1 file.
7. Open iTunes 10.5, connect your device and use “Shift + Restore” button and give it the custom iOS 5.0.1 beta 1 file you cooked earlier (should be on your desktop).
8. Wait for iTunes to restore the device to iOS 5.0.1 custom .ipsw file.
9. Activate your phone with an orignal simcard from the network it was locked when sold and you are ready unlock with rebel micro simcards after activation is complete.
10. Point to note when unlocking iOs 5.01. in the instructions all is the same but at the point when the rebel menu loads and you press accept and in the top left hand corner of the screen you wont see the one bar like this . . instead you will see the message no service. proceed in the same way as in the user guide and all will work and get network.
11. You can use other tools also to perform the baseband downgrade to 04.10.01 on a mac and use tools like redsnow.