Here’s a list of 26 common issues with Dahua NVRs, organized for your reference:

1. Device fails to start after powering on

• Incorrect power input.
• Poor connection of the power cable.
• Power supply is damaged.
• Program upgrade error.
• Hard drive damage or cable issue.
• Compatibility issue with new hard drives like Seagate DB35.1, DB35.2, SV35, Maxtor 17th generation, etc. Upgrading to the latest firmware resolves this.
• Front panel failure.
• Mainboard failure.

2. Device reboots automatically or frequently crashes after a few minutes

• Unstable or low input voltage.
• Incorrect hard drive jumper settings.
• Bad sectors on the hard drive or faulty cable.
• Insufficient power from the power supply.
• Unstable video signal from the front-end device.
• Poor heat dissipation, excessive dust, or a harsh operating environment.
• Hardware failure.

3. Hard drive not detected after startup

• Hard drive power cable is not connected.
• Faulty hard drive cable.
• Incorrect jumper settings on the hard drive.
• Hard drive failure.
• Faulty SATA port on the mainboard.

4. No video output on single, multiple, or all channels

• Program mismatch, upgrade to the correct firmware.
• Image brightness set to 0, restore to default settings.
• Channel protection (or screen saver) activated.
• Hardware failure.

5. Unable to find recorded video during local playback

• Incorrect hard drive data cable or jumper settings.
• Faulty hard drive.
• Upgraded to a firmware with a different file system.
• Desired video has been overwritten.
• Recording has not been enabled.

6. Local playback displays garbled images

• Program data reading error, small bitrate, and mosaic effects during playback. Typically fixed by restarting the device.
• Incorrect hard drive data cable or jumper settings.
• Hard drive failure.
• Hardware failure.

7. Incorrect time display

• Incorrect settings.
• Poor battery contact or low voltage.
• Faulty crystal oscillator.

8. Unable to control PTZ (Pan-Tilt-Zoom) camera

• Front-end PTZ failure.
• Incorrect PTZ decoder settings, wiring, or installation.
• Incorrect wiring.
• Incorrect device PTZ settings.
• PTZ decoder and device protocol mismatch.
• PTZ decoder and device address mismatch.
• When using multiple decoders, add a 120Ω resistor at the far end of the A/B cable to eliminate reflections and impedance mismatches, otherwise PTZ control may be unstable.
• Excessive distance.

9. Client or Web cannot log in

• Client installation or display issues, operating system version too low.
• ActiveX control blocked.
• DirectX graphics acceleration engine not installed or outdated graphics card drivers.
• Network connection failure.
• Network settings issue.
• Incorrect username and password.
• Client version incompatible with device firmware version.

10. Network preview image or recorded file playback shows mosaics or no image

• Poor network stability.
• Limited client resources.
• User lacks preview permission.

11. Unstable network connection

• Network instability.
• IP address conflict.
• MAC address conflict.
• Faulty network card on the computer or device.

12. Recording/Burn/USB backup errors

• Burner and hard drive connected on the same data cable.
• Backup process uses excessive CPU resources; stop recording before backing up.
• Data size exceeds backup device capacity, causing errors.
• Incompatible backup device.
• Backup device failure.

13. Keyboard unable to control the device

• Incorrect serial port settings.
• Incorrect address.
• Insufficient power supply when using multiple converters; each converter needs its own power supply.
• Excessive transmission distance.

14. Unable to disarm the alarm signal

• Incorrect alarm settings.
• Manual alarm output activation.
• Faulty or incorrect input device connection.
• Issue with specific firmware versions, upgrade to resolve.

15. Alarm not triggering

• Incorrect alarm settings.
• Incorrect alarm wiring.
• Incorrect alarm input signal.
• Alarm device connected to two loops simultaneously.

16. Insufficient video storage time

• Front-end camera quality issues, dirty lenses, backlit installation, aperture lens not adjusted properly, etc., leading to high bitrate.
• Insufficient hard drive capacity.
• Hard drive failure.

17. Downloaded files won’t play

• Media player not installed.
• Missing or outdated DirectX graphics acceleration engine.
• When converting to AVI format and using MEDIA PLAYER, the computer does not have the DivX503Bundle.exe plugin.
• Windows XP requires installing DivX503Bundle.exe and ffdsho-2004 1012.exe plugins.

18. No image, black screen

• Incorrect IP of the remote device.
• Incorrect port number of the remote device.
• Incorrect username/password for remote device.
• Network connection issue with the remote device.

19. Incomplete display interface

• Check the current resolution and ensure the display supports the resolution. For example, if the resolution is 1920×1080, the monitor must support 1920×1080 resolution.

20. No HDMI output on the display

• Check if the display is working in HDMI mode.
• Check if the HDMI cable is working correctly.

21. Client multi-channel preview image lags

• Check network bandwidth; multi-channel preview requires higher bandwidth, at least 100 Mbps.
• Check PC performance; multi-channel decoding requires decent PC performance. A PC decoding 16 channels should have at least a 4-core CPU, 2GB RAM, and a dedicated graphics card with 256MB of memory.

22. IPC (IP Camera) unable to connect

• Check if the power supply is connected.
• Ensure the IPC network is stable and connected.
• Ensure compatibility between IPC program and storage device.
• Confirm IPC has fully started.
• Check if IPC is in the blacklist.
• Ensure the IPC isn’t overloaded with too many connections, causing failure to transmit images.
• For third-party IPCs, confirm the IPC’s port and time zone match the device.
• Ensure the current network environment is stable.

23. Display resolution set to 1080P, but monitor does not support it

• Power off, then power on again while holding the Fn key. After 5 seconds, release it, and the device will revert to the default resolution.

24. Unable to find “Add Remote Device” option on the Web interface after login

• Clear the web control cache and reload.

25. IP and gateway set correctly, can access the internet via the router, but cannot access after reboot

• After rebooting, check if the device can ping the gateway. If not, use Telnet and the “ifconfig -a” command to check the device’s IP address. If the mask and gateway change, upgrade the firmware and test again.

26. Connecting to a VGA monitor shows the main stream instead of the sub stream in multi-split mode

• 32-channel devices display the sub stream on 9 or 16 splits.
• 4/8/16-channel devices display the main stream on all splits.