Edge will not work, Go to your file explorer, windows---> system32---you should see a "webrec" folder. Delete it, that's where the plugins reside. Restart IE and it will re install the plugins for IE, They ALL have to install and need permission,I think it will prompt you like 5 times. If that does not work, again go to the Dahua site and download a copy of SmartPSS , That does not use plugins and add your NVR Only to it, you will see a list of your cams and you should be able to see them.
I also remember someplace here where other people had this issue and a firmware update fixed this but my memory is not so great. One other thing is when you log in direct with a browser to the NVR, under system you should see a display tab, check your resolution settings, if your monitor is older, you might have to kick the resolution down.