xbox error ( urgent !)

[Calazar]

i have tryed:
to boot from a cd:nothing
check the cablesk
to remove the chip: the error still occures

(i have changed the xboxdash.xbe, but i can't understand why is this a problem, i don't have access to change anything now. The xbox worked fine )

The only thing i can think about is the HD .Is there a problem to get the xbox to microsoft, to fix it (ones i have removed the chip, not the files to hd althought) ?