Place the firmware file (.esf) in a folder called ‘autoupgrade’ on the root of a USB flash drive 

Turn on the DVR and let it go into record.  (I.E. Start the bus)

Place the USB flash drive the DVR, the DVR will automatically begin upgrading.

WARNING: Do not disturb the flash drive until the DVR goes back into record, pulling the flash drive during the update could cause the DVR to be required to be sent back to the factory for recovery.