1) Check if you load the activeX when you login.
If you use Internet Explorer, you need run the activeX (ActiveX Control Module) when you login the camera. When the activeX prompts you, please install it, do not block it, or you will not see living video. About how to load the activeX, please see the guide of “How to load activeX in Windows7 computer”.
2) Check if the firewall or anti-virus software blocks the activeX or not.
If you have firewall or anti-virus software on your computer, they may block the activeX. Please disable them briefly and try to load the activeX.
3) Check if you choose the correct login mode or not.
There are two login mode, one is for IE browser (ActiveX mode), the other is for firefox, google chrome, safari browser (Server Push mode), if you choose the wrong login mode, you cannot see living video, instead of black screen.
4) If you have already tried all these suggestions above, but still cannot see video, please change a port number to try, do not use port 80, change to port 81, 82, 8005. etc. As port 80 may be used by other applications or process.