Ruu-shooter-u-ics-35-s-htc-asia-tw-3.28.709.3-radio-11.77.3504.00u-11.25.3504.06-m-release-270747-signed.exe -

This happens if you try to flash an RUU from the wrong region (e.g., trying to flash the Taiwan RUU on a European device). You may need to change your CID to HTC__621 or have S-OFF (Security Off) status to bypass this.

Fixing a device that is stuck in a boot loop or won't start. This happens if you try to flash an

This often indicates the bootloader is unlocked. Use the command fastboot oem lock in the ADB terminal to relock it before trying again. This happens if you try to flash an