3GS Pwned on iOS 4.0, gets error 21 when restoring custom 4.1 firmware

Title says it all:

My 3GS (early bootrom, on official carrier, unlocked and jailbroken on iOS 4.0 with Pwnagetool previously). Now trying to update it to a jailbroken 4.1

On a Mac, I run Pwnagetool 4.1 to create the custom firmware as before.
I then alt-restore in iTunes and get unknown error 21. So, I transfer the 4.1 ipsw custom firmware file to my Windows 7 PC (this one is what I used previously to restore the custom 4.0 firmware) and get the exact same error 21.

So, do I need to get into (pwnagetool) DFU to restore the custom firmware in iTunes 10? I tried that, and after a few attempts it never was successfully put into DFU mode.

Each time it gets error 21, I connect to TinyUmbrella and use 'Exit Recovery' to get the 3GS to wake up again.

4.2 is coming, so I thought I would upgrade soon and save my SHSH blobs (got em saved for 4.0, 3.1, 3.0 too).

Wondering what I need to do or what I am doing wrong.

Quote:

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Originally Posted by zuzzu

So, do I need to get into (pwnagetool) DFU to restore the custom firmware in iTunes 10? I tried that, and after a few attempts it never was successfully put into DFU mode.

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Yes, you need the "special" pwnagetool DFU mode to restore 4.1.x custom IPSW.

A few suggestions:

1. Pwnagetool 4.1.2 is the latest version of Pwnagetool for making 4.1 custom IPSW, fixes a few bugs. http://blog.iphone-dev.org/post/1359...20102010-event
2. If for some strange reason you cannot get the pwnagetool DFU mode to work. Try redsn0w 0.9.6b2 redsn0w 0.9.6 BETA [iPhone Dev Team] on windows with a custom IPSW made via pwnagetool on mac. It has an option to enable the special "dfu mode" and then you can simply shift-click restore.
3. Error 21 is an expected error when using custom 4.1 IPSW and you aren't in the "special dfu mode" - your iPhone hasn't been updated at all. So don't panic. Just hold down power and home until the iPhone reboots (this will allow your iPhone to boot normally with the current OS) and try the special DFU mode again.

Quote:

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Originally Posted by zuzzu

4.2 is coming, so I thought I would upgrade soon and save my SHSH blobs (got em saved for 4.0, 3.1, 3.0 too).

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You don't need to upgrade to save your SHSH blobs. A common misconception is that you need to be running say 4.1 to save a 4.1 SHSH blob. That is not true.

Simply connect your iPhone (in normal mode) to your mac/PC.
Download unpack/install and run http://thefirmwareumbrella.blogspot.com/
Make sure it detects your iPhone and then click "save my SHSH"

Note that Cydia has temporarily disabled the option where it displays on the cydia home screen that you have SHSH on file for specific iOS versions. The SHSH are still there on Cydia's server, the display has just been disabled for performance reasons. Display of SHSH information on the Cydia home screen will most likely return once the demand has slowed and the performance problems have been solved.

Olethros,

Thanks. I used redsn0w 0.9.6b2 on Windows 7 x64 to get into DFU mode, then used by pwnagetool-created IPSW file, and it worked like a charm.

Worked perfectly I DFU'd with pownage and it finally allowed me to restore. Thanks again for the help!