put this file on your sd card (its ra recovery 2.1.1 the files at the bottom attached to this post)
load hboot hold power and vol down
ill you scan for the file
then it will ask you to update
vol up for yes
then go in to recovery
hold power and vol down to get in to hboot
once in hoboot vol down to get to recovery
once in recovery do a scroll the restore/backup
do a nand backup(this will backup everything including your RSA key)
or if you wanna back up the key its self use this
http://forum.ppcgeeks.com/htc-evo-4g...-oem-roms.html
no to update you rom
DOWNLOAD
MIRROR
[All-In-One Update, INCLUDES Updated Baseband & Wimax Radios + PRI 1.90_003, Uninstallable apps]
this file will replace the other pc36img.zip i had you install before
INSTALLATION INSTRUCTIONS: (For "All-In-One" update)
-Copy the PC36IMG.zip to the root of your SD Card
-Power off your phone
-While holding the VOLUME DOWN button, power on the phone
-Your phone will enter bootloader and automatically scan the file and prompt you to update
-Press VOLUME UP the install the update
-When completed, press VOLUME UP to reboot the phone
this file has all the update radios