IP Cam - Main connection failed.

Hi I have small issue.

I have 2 cameras and forwarding RSTP port (to stream video) and HTTP to manage cameras.

So, managing and streaming works fine of all of this two cameras.

But ONLY with one I have one issue. When I log in to web interface I have message "main connection failed" and I don't see video on web interface. I need this to set detection area.

Someone can tell me how to fix it ? And what's going on ?

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Solved ! I forwarded TCP port.

I had a strange issue exactly like this when I upgraded to Windows 10. Regardless of which browser I was using, all streams in the web gui would fail. Reinstalling the plug-in did nothing, so I almost gave up till I tried reinstalling the NIC driver. For some reason, the network driver Windows 10 installed by default was affecting the browser and the driver was out of date. Once I downloaded and installed the up-to-date drive for the Asus motherboard, the browser began working like normal.