since your phone is still s on,we will need to know what build you were on in order to recomend the correct ruu.
if youre on the newest firmware,then you will need this one,wich is a .exe format:
Shipped ROMs
youll need to start the ruu program with the phone in fastboot mode(evidenced by
fastboot usb in the bootloader screen)
another option is to install a zip file in hboot:
Shipped ROMs
that file can be renamed "PD98IMG" and placed on a FAT32 formatted(very important!) sd card.
hopefully that will get your phone up and runing.
once you are back to working order,id recomend
NOT to use the AAHK. it is no longer supported,and the links the program needs are no longer valid.
attn1 has provided a new hack,wich i have detailed as much as possible here:
http://androidforums.com/desire-hd-...-s-off-simunlock-supercid-inspire-4g-dhd.html
just holler if you have further questions