Applying unofficial firmware usually voids your manufacturer's warranty. Always ensure you are using a fix file generated specifically for your machine's Serial and CRUM numbers to avoid "bricking" the printer.
The printer's LEDs will flash during the update. Do not turn off the printer or unplug the cable until it automatically reboots (usually takes 1–2 minutes).
The specific software version currently running on the printer (e.g., V3.00.01.05).