Can you still get into fastboot.
download a file from here the matches your cid and model number
http://www.htc1guru.com/downloads/ruu-zip-downloads/
Then in fastboot write this command "fastboot oem rebootRUU"
Your phone should have a black screen, now place the downloaded file in your adb/fastboot folder
then input this command "fastboot flash zip file-name-here.zip
and your phone will be back to stock