I successfully Rooted my Thunderbolt. It is working fine. Yesterday, a friend asked me to help him Root his Thunderbolt. We followed the same process that I did. Everything looked OK and S-Off appeared on the Bootloader screen. I installed Superuser, from the Market and Rom Manager. When I launched Superuser, it prompted me to install an Update. I then received the following message: An error occurred and su was not updated. A zip file (su-2.3.1-bin-signed.zip) has been placed on you sdcard. Please reboot into recovery mode and flash it to update your su binary. Rom Manager indicates I do not have Root permissions. I reboot into the Bootloader menu and choose Recovery. All I get is an image of a phone and a Red Triangle. I have to pull the battery to reboot. The phone boots normally and works fine, but no Root permissions. The zip file I referenced is on the SD card but I do not know how to Flash it.