Use a drive 32GB or smaller, formatted to FAT32 .
If your device is a Dahua-branded unit, use their official firmware search tool. Download Firmware DVR DHUA 7004AHD (AVR8283 rar
If you can tell me the or the Hardware ID found in your DVR's "Version" menu, I can help you find the exact download link for your specific board version. Firmware Update - Dahua Wiki Use a drive 32GB or smaller, formatted to FAT32
Boot the DVR and go to Main Menu > System > Info > Version . Write down the Build Date and Hardware ID . Search Trusted Repositories: Firmware Update - Dahua Wiki Boot the DVR
Place the firmware file in the root directory (not inside a folder). Insert & Upgrade: Plug the USB into the DVR's USB port. Navigate to Main Menu > System > Upgrade . Select the file and click Start .