ARGH!!! Dont give up. I've got exactly the same issue. Caused by pretty much the same error on my behalf.
Can boot to HBOOT (vol DOWN, press power)
Can get into recovery (from HBOOT select RECOVERY, wait for red triangle, hold vol UP, press power)
Have tried heaps of different PB99IMG.zip's and heaps of update.zip's with no luck.
Basically, HTC/Telstra updated HBOOT to version 0.93 and enabled S-ON (security on) which basically leaves you with no way of upgrading or downgrading HBOOT. AlphaDev have made an excellent boot CD to disable (sort of) S-ON but you have to be in USB debugging to run it (same with Revoked of course). When the furthest you can get is HBOOT also FASTBOOT and the built in recovery I mentioned earlier.
I CAN use fastboot commands from my PC but CAN'T use any adb commands as adb isnt detecting the device (no USB debugging again).
Can boot to HBOOT (vol DOWN, press power)
Can get into recovery (from HBOOT select RECOVERY, wait for red triangle, hold vol UP, press power)
Have tried heaps of different PB99IMG.zip's and heaps of update.zip's with no luck.
Basically, HTC/Telstra updated HBOOT to version 0.93 and enabled S-ON (security on) which basically leaves you with no way of upgrading or downgrading HBOOT. AlphaDev have made an excellent boot CD to disable (sort of) S-ON but you have to be in USB debugging to run it (same with Revoked of course). When the furthest you can get is HBOOT also FASTBOOT and the built in recovery I mentioned earlier.
I CAN use fastboot commands from my PC but CAN'T use any adb commands as adb isnt detecting the device (no USB debugging again).