Description
There is No Video after connecting the NVR to Monitor via HDMI/VGA. But the NVR web page can be accessed.
Generally, after connecting, the monitor will display the corresponding interface.
Cause
1. HDMI2/VGA2 port on 8000 Series NVR
2. HDMI Compatible Mode setting problem
Resolution
1. HDMI2/VGA2 on 8000 Series NVR
Confirm whether the NVR is connected to the monitor through HDMI2 port.
Milesight 4k H.265 Pro NVR 8000 has two HDMI ports and two VGA ports. Generally, the HDMI2/VGA2 is disabled.
If you encounter such case that the NVR is connected to the monitor though HDMI2 port and there is no video displayed, it might be caused by the disabled HDMI2 port, you can change to the NVR HDMI1 port or enable HDMI2/VGA2 on the NVR web page to solve this problem. 
Note:
After HDMI2/VGA2 is enabled, the screen will still be black, if there is no camera added to the NVR.
In this case, you can try to double-click the mouse wheel on the main screen, and then video source will switch to the HDMI2 from HDMI1 port. Also, you can right-click on main screen to open Display Info to distinguish whether the HDMI2/VGA2 output is normal.
2. HDMI Compatible Mode setting problem
Switch the HDMI Compatible Mode to test if the problem is solved.
Theoretically, this function is used to be compatible with different monitor manufacturers and generally it is enabled. But, some monitor manufacturers have unconventional HDMI settings, it may cause no video on Local Monitor by this option.
3. External factors
3.1 HDMI/VGA Cable Issue
Make sure that the HDMI/VGA cable is available. If possible, you can exchange a good one cable to test.
By the way, the HDMI 1 port can support up to 4K resolution. We recommend that using HDMI cable which supports 4K resolution as your prime choice.
3.2 Monitor Issue
Check whether the HDMI/VGA port of the monitor is available.
Some monitors have multiple HDMI/VGA ports, you can exchange other ports to verify.
If not, you can connect the port to other devices to test.
Note:
For monitors with multiple HDMI/VGA ports, please make sure the program source corresponds to the HDMI/VGA port. 
4. NVR HDMI/VGA port failure
Besides above problems, the No Video on Local Monitor might be caused by NVR HDMI/VGA port failure.
If above resolutions do not resolve the problem, please create a Ticket and attach the MAC address of faulty NVR (Necessary) to Milesight support for further help.
Note:
l Please check whether the NVR HDMI/VGA port is physically damaged. If so, it is better to provide faulty photos to Milesight Support.
l For 5000/7000/8000 series NVRs, these NVRs have multiple Video Output interfaces. If possible, you can exchange to verify whether the interface is faulty.
Others
None