This guide is to unlock iPhone 3G with baseband 05.08 running iPhone OS v.4.0. First of all, you need to Jailbreak your iPhone using Redsn0w. Links provided at the end of the post! once you are done jailbreaking your iPhone, follow these steps to unlock your iPhone 3G.
1. Launch Cydia from your springboard, and go to systems under section tab
2. Press to select 3G Fuzzyband Downgrader from the list of packages & click on install.
3. After installation is completed successfully return to cydia and press home button and launch Fuzzyband.
4. Note: If you have the 5.08 bootloader you will be able to downgrade from baseband 05.13.01. Press the Downgrade button to begin downgrading your baseband.
5. Once the downgrade has completed successfully you will be displayed a Done! message saying, “I Haz Downgrade!”
6. Open Cydia and add a new source. Go to manage tab.
7. Click on “Edit” and then on “Add”. You will be prompted to enter a url source. Type “http://repo666.ultrasn0w.com” and click on “Add Source”.
8. After successfully adding repository search for ultrasn0w in cydia and install the application
9. Restart your iPhone.
10. And yup! You’ve unlocked your iPhone 3G. Happy OS 4.0 .
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