Bios Question

[LunchLady]

Hey everybody, i just have a quick question regarding my BIOS. I run a xbox with a messiah X chip....old eh. do you know if its possible to flash it with any of the new bioses? i have tried to flash it and all that happened was it gave me this error:
!! Flash Not Writable !! what does this mean?!?! an also i have had troubles backing up madden 2004, it just wont go even after i patched it. and MOH Rising Sun is giving me an invalid block size? do you know what i can do to fix this. i used the newest version of gdfimage to make a gdf'ed iso.

Any help is great
Thanks

-LunchLady-