How to fix the validation error for backup CID when running unrevoked3.21...

PLEASE DO NOT COPY OR LINK TO THIS GUIDE OUTSIDE OF THE #unrevokedtest CHANNEL.

This is a quick 'n' dirty guide for ADVANCED USERS ONLY.

*** Proceed at entirely your own risk. ***

(If at any step something looks different or wrong from what's indicated in the guide then STOP and seek assistance.)

adb shell
$ /system/__unrevoked_su
# cat /dev/mtd/mtd0 > /sdcard/misc.img
# getprop ro.cid
HTC__001 <---- remember this
# exit
adb pull /sdcard/misc.img

Now open a hex editor like ghex2, HxD, xvi32 and at the start of the file (position 0) you probably have all FF's.

At position 0 enter the cid (HTC__001) from above then follow that with hex '00'... so the hex string looks something like: "48 54 43 5F 5F 30 30 31 00".

Save the file and exit the hex editor.

adb push misc.img /sdcard/new-misc.img
adb shell
$ /system/__unrevoked_su
# /data/local/flash_image misc /sdcard/new-misc.img
# exit

Now re-run unrevoked and it should now complete successfully.

Credit: thanks to joshua_ (of unrevoked) for some information on how their rooting process works.

Written by: kmdm (irc.freenode.net).