Make sure you are using Internet Explorer, not Edge, not Chrome with the IE plug-in, not FireFox. Plain ole Internet Explorer that is baked into Windows 10, you simply have to type in Explorer and it will come up and you do not even need to download it. In many cases, not using IE results in the settings not saving and sticking.
As many find out...using Chrome browser interferes with Dahua camera GUI where as things just do not work right after hitting save (FW updates, auto-tracking seconds, no IVS lines on main view, etc). For those that do not know....do not use Chrome. Most folks use the older Microsoft IE browser...
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