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.