: Always download firmware directly from the ZKTeco Download Center or your regional support page (e.g., ZKTeco India or ZKTeco Europe ).
Perform a hardware reset using the physical reset button, or contact ZKTeco support for a bootloader recovery tool. Drive partition format is incompatible. zkteco k40 pro firmware top download
Once you have verified and downloaded the correct file, use one of the two standard methods below to apply the update. Method A: USB Flash Drive Upgrade (Recommended) : Always download firmware directly from the ZKTeco