In case you have unlocked your iPhone 3G/3GS by flashing iPad baseband 6.15.00 with ultrasn0w 1.2 on iOS 4.2.1, and have issues while restoring your device, follow the simple guide posted by Sherif Hashim, the developer behind ultrasn0w unlock tool, showing how to restore your iPhone 3G/3GS and resolve all the issues.

Note:

To restore your iPhone 3G/GS from 4.2.1 to 4.1, you must have your SHSH blobs saved for iOS 4.1.

How To Downgrade iPhone 3G/3GS on iOS 4.2.1 (BB 06.15.00) to iOS 4.1:

For PwnageTool users:

A : If you are on Mac and use PwnageTool: If you used pwnage tool then you will have to create a “new” custom 4.1 or 4.2.1 and say “No” when you are offered the BB update to 6.15.00 since you already have it, then build the custom ipsw and restore to that.

For Redsn0w users:

B : If you use(d) Redsn0w:

B.1: If you are currently on 4.1, then you can restore to official 4.1 again, and when you see error 1015 pop-up, you kick your device out of recovery mode using TinyUmbrella, use redsn0w and don’t check “ipad BB update” because you already have that Here Is How To Restore iPhone 3G And iPhone 3GS While On Baseband 06.15.00 And Having Issues icon smile

B.2: If you are currently on 4.2.1 then you’ll have to restore back to 4.1 (because 4.2.1 will not allow you to kick the phone out of recovery when 1015 occurs due to the silly BB / iOS mismatch check added there) , then do the same steps as CASE-1.

How to upgrade to iOS 4.2.1:

If you want to go again to 4.2.1 your only way is to use a custom 4.2.1 done by pwnage tool in the same steps mentioned in A .

Try this methods listed above to restore your device between 4.2.1 and 4.1, it’s worth trying. And, don’t forget to tell us about your experience in the comments section below.

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[Source: Sherif Hasim(twitter)]

Related Posts:

• [How To] Jailbreak And Hactivate iPhone 3G/3GS With Redsn0w 0.9.6b6 And SAM
• [How To] Update iPhone 3G / 3GS Baseband to 06.15.00 With PwnageTool 4.1.3
• iPhone 3G/3GS Unlock GPS Issue Progress and RedSn0w Update
• Battery Issues Reported After Unlocking iPhone 3G/3GS With Ultrasn0w 1.2
• Apple Puts Baseband Requirement In iOS 4.2.1; Jailbreakers & Unlockers Beware
• [How To] Downgrade iOS 4.2.1 To Older Firmware For iPhone, iPod Touch And iPad
• TinyUmbrella Updated To 4.21.01; Offers Support For iOS 4.2.1
• [How To] Save SHSH Blobs Directly From iPhone, iPad, iPod touch Using iSHSHit

Authors: _GadgetNews

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