If the phone is completely dead (no LED), you may need to open the back cover and short the "TP" (Test Point) on the motherboard. This voids warranty and requires technical skill.
Click the (Square icon) in the tool, unplug your USB cable, and hold down the Power button to turn on your device. Note that the initial boot up can take up to 10 minutes. Troubleshooting Common Flashing Failures Firmware ZTE Blade V30 Vita
Reinstall drivers or try a different USB port/cable. If the phone is completely dead (no LED),
Recovers the device if it refuses to power on due to a corrupted operating system (Dead Boot). Note that the initial boot up can take up to 10 minutes
ZTE does not have a centralized public download server like Samsung or Google. However, you can find legitimate stock firmware through:
Once completed, the progress bar turns green and displays a or Finish message.
Flashing wipes your internal storage completely. Back up all photos, contacts, and personal documents to a cloud service or an external computer.