Stock Android on Nexus S - "invalid magic code" I have a Nexus S (2.3.3, GRI54/I9023, bootloader unlocked, clockworkmod recovery installed, rooted) and I'm trying to flash it with a stock system.img that I built myself (no modifications - yet).

To make the stock Android build, I followed the instructions for making a build found at http://source.android.com/source/download.html. The build was successful and the system does work when run on the emulator.

To flash the ROM, I connect the phone, boot with Volume up + Power, connect USB and type

fastboot flash system system.img


The response that is shown on the phone is

Invalid magic code 0x00000003


What does this mean? What's wrong?
I believe you need the stock recovery, based on http://2chnull.info/r/smartphone/1292830738/801-900.  You can get back to stock recovery easily, for example follow this thread: http://forum.xda-developers.com/showthread.php?t=884093