This is a pre-release version of iPhone 3G OS 3.0. This is the original .IPSW file from Apple servers. This can be installed on any iPhone 3G but you need to have your iPhone registered to be able to sync with your PC/Mac via iTunes.
To Roll Back To older OS Version Please do the Following:
1. Open Up iTunes
2. Have Your iPhone Connected To Your Computer
3. Hold Down The Power/Sleep Button And The Home Button For Exactly 10 Seconds.
4. Then Release The Power/Sleep Button And Continue To Hold The Home Button Until iTunes Brings Up A Message Saying Your iPhone Is In DFU Mode.
5. Click Ok Or Whatever It Is So That It Closes That Popup.
6. Hold Shift Then Click Restore.
7.Then Make sure You Have Downloaded the ISPW Firmware Called: iPhone1,2_2.2_5G77_Restore. (MAKE SURE ITS iPhone1,2_2.2_5G77_Restore AND NOT iPhone1,1_2.2_5G77_Restore CAUSE THAT FOR THE 2G IPHONE).
8. Let It Restore Once Its Finished You Will Get An Error Thats Normal It Will Most Likely Be 1015 Or Something Like That.
9. Download Quick Pwn 2.2.1.
10. Then Open Up Quick Pwn With You iPhone Connected To Your PC And It will then Say That You Need To Hold The Power/Sleep Button And The Home button For Exactly 15 Seconds Then Release The Power/Sleep Button And Continue To Hold The Home Button For 2 Seconds. This will Then boot your iPhone To the Emergency Call screen.
11.Open up iTunes And Let It Activate Your iPhone.
12. Then Restore your iPhone From A Previous Backup If you Have One.
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