This is the safest method to ensure your device has the latest official features and security patches. Check for Updates Software updates Manual Check to see if a newer version is available from HTC. : If an update appears, tap . It is highly recommended to use a Wi-Fi connection to avoid high data charges. : Once downloaded, select Install now . Your phone will restart to apply the changes. 2. Manual Firmware Change (Flashing)

Regular firmware updates are essential to ensure your device stays secure, stable, and performs at its best. By updating your HTC One X9, you'll enjoy a better user experience, improved performance, and enhanced security features.

A firmware change update is riskier than a standard app update. If interrupted, you can your HTC One X9 (turn it into an expensive paperweight). Follow these precautions:

| | Cause | Fix | | :--- | :--- | :--- | | FAILED (remote: 12 signature verify fail) | Mismatched CID or unsigned firmware | Re-download the correct signed RUU for your exact CID. | | Sending ‘zip’… (OKAY) then FAILED | Corrupted download | Re-download firmware.zip and check MD5 checksum. | | Phone stuck on HTC logo after flash | Old ROM incompatible with new firmware | You must re-flash your ROM (custom or stock) after firmware update. | | No cellular signal (IMEI unknown) | Radio partition flash incomplete | Flash only the radio firmware separately: fastboot flash radio radio.img | | Touch screen inverted or not working | Touch panel firmware version mismatch | Revert to old TP firmware (extract from your original RUU). |

Do use random firmware from untrusted sources. Good sources: