Format your USB to FAT32. Step 2: Download the firmware .bin or .img file from the official source. Step 3: Copy the file to the root directory of the USB (not inside any folder). Rename it if required by the manufacturer (e.g., update.bin ). Step 4: Power off the DVR using the physical power switch on the back. Step 5: Insert the USB drive into the DVR’s USB port (usually the front panel). Step 6: Power on the DVR while repeatedly tapping the ESC or Enter key (depending on the bootloader) to enter the "Update Mode." Alternate Method: Boot normally, go to Menu > System > Upgrade > USB Upgrade . Step 7: Select the file and click "Upgrade." Do NOT touch the DVR or turn off power. Step 8: Wait for the "Upgrade Successful" message. The DVR will reboot automatically. Step 9: Perform a "Factory Reset" after the update ( Menu > Factory Default ) and then restore your configuration backup.