I am having Problems unrooting htc evo

[capone0914]

I Rooted my phone a few months ago. I realize if your phone is rooted u can not do the updates for your evo phone. I am on android version 2.2/ software # 3.29651.5. I downloaded ruu supersonic sprint stock with the same software #. I connect phone to usb and comp 32bit windows 7 dell insperion 1501. It goes thru the process just fine till it gets to the bootloader part. It makes the phone black with htc logo. On comp screen it says rebooting to bootloader and then waiting for bootloader. It does that for bout 3min then i get an error 171 connection error. Its connected, there r no problems with the connection. The screen on phone is stuck in black with htc logo on it. I diconnect from comp and get this white screen that says supersonic evtz-3 ship s-off
hboot-0.97.000
microp-041f and sum other stuff. What am i doing wrong? Why can i not go back to stock?