AGI Security SYS-16A901 How to update firmware on AvTech DVR - Manual (Page 3)

Unzip the file to your thumb drive if you’re upgrading at the DVR. If the file is
inside a folder move it the root directory of the drive. You should be able to open
the thumb drive and see the file without opening anymore folders.
At the DVR main menu go to Advanced Configuration>System
Information>Tools>Upgrade. It will ask you to insert the USB Drive if you have not
done so already. Then you will get a prompt to save current settings, click yes if
you want to keep the current configuration. The DVR will go through the update
process and reboot.