I tried to update my friends HTC Desire HD from 2.3.5 to 4.2.2. Let me point out that my experience with ROM flashing and rooting is limited.
Since he still had stock ROM my plan was to unlock bootloader, root the device, flash CWM and flash custom some custom ROM(same way I have done before with HTC wildfire S)
I used htcdev to unlock bootloader and that went well.
After that I tried to root using HTC Quick Root. Rooting failed with message device is missing Insecure boot.img. In order to fix this I tried to flash boot.img from fastboot using folllowing command: fastboot flash image boot.img
After this device never booted again. It starts to boot showing green HTC logo but soon goes to image of phone with red triangle and exclamation.
I have red many posts about this problem and possible solutions but non of it worked for me.
As I understand it solution is to flash RUU or manually flash recovery.img but I need some help on how to proceed.
RUU install is failing with error140bootloader version error.
*** UNLOCKED ***
ACE PVT SHIP S-ON RL
DEC 22 2011, 14:28:19
Any help is appreciated.