Help Me Understand Somethig Here., The whole, you cant JTag stff si confusing me.. Options

[BladeWing]

Ok, i have my own jtagged 360 and am able to run homebrew on it and all, but i never really understood just what stops us from using xell/Jtag on an 8xxx xbox.

They say that M$ has add something to the nand that blocks the hack (If that was true, a nand re-write would be able to reverse it), as well as blown (off) e-fuses. and that the cb/cd is too high.

Can somebody just please explain just exactly stops the hack, as everywhere that says, ''no not possible'' just says, the 3 above.

Thanks for the time reading
BladeWing

[vb_encryption_vb]

MS blew the efuses, which causes no more homebrew on 8xxx. Once the efuses are blown JTAG just simply won't work anymore. XBR uses whats called "virtual efuses" to keep the JTAG active... It has nothing to do with the nand, as the nand is what we rewrite with xbr anyways.

[BladeWing]

Thank you, now i understand entirely.

[Martinchris23]

MS blew the efuses, which causes no more homebrew on 8xxx. Once the efuses are blown JTAG just simply won't work anymore. XBR uses whats called "virtual efuses" to keep the JTAG active... It has nothing to do with the nand, as the nand is what we rewrite with xbr anyways.

This is my understanding:

The exploit is possible due to a vulnerability in the bootloader (CB). Microsoft have since fixed this exploit by forcing an updated version in dashboards over v2.0.8xxx (as well as updates via MS Service Centers from June 2009). This alone shouldn't be a problem as you could still downgrade and exploit. However, they also burned the eFuse responsible for the CB version, meaning you cannot use an exploited bootloader.