If you have followed all nine solutions and the error persists, your phone's eMMC (internal storage) may be physically dead, or the firehose loader you are using does not match your device's CPU (a separate error often misreported as a port handle failure).
The "Failed to open COM port handle" error in typically occurs because the software cannot establish a clean connection with your device's communication port . This is often due to improper driver installation, incorrect device mode (EDL), or another process using the port. Common Causes qfil failed to open com port handle