Hey, i'm trying to fix an xbox right now that has a really odd problem. It's a v 1.0 xbox with a xecutor 2.2 modchip installed. Whenever I turn it on with the modchip off, it boots up to one of those MS error screens, but there is no error code in the corner, when I boot it with the modchip on, then it boots to an error screen with a 16 in the corner. So i thought, ok, it's just a dashboard problem. So i hooked up my DVD drive to the xbox, same way I fixed my other xbox with a dashboard problem and loaded the very same boot disc I used on the other one which all worked fine on my xbox. This time it boots up to the error screen with a 21 in the corner. I dont know what's goin on. What does the error screen with no error code in the corner mean? Thanks

if its a larger hard drive make sure its locked
the boot sequence might not be right
the dashboard file might not be the same name as the one in the boot sequence

This should be the problem

How do I make sure it's locked? I tried booting from a CD and it still didn't work.

error 21 could mean some parts of the dash are missing, or more likley your hard drive isn't locked

Dashboard error. You have a couple options:

1. Reflash the X2.2 chip with a recent "clock fix" BIOS (I recommend X2 4981.06) then you shoild be able to boot your boot disc.

2. Plug in the stock hard drive or the unlocked HDD from another working Xbox, boot with the modchip on. Then go to the MS Dash, set your clock, and power down. Make sure you leave the Xbox plugged in. Put the old HDD back in and boot your boot disc.