The short answer
Dahua’s documented RTSP format separates channel from subtype. Match camera versus recorder and select the stream deliberately instead of copying a URL from another installation.
Work through the checks
Identify the camera by model, hardware revision, firmware and MAC address. Keep this inventory separate from passwords; two devices with similar names may expose different protocols.
For the documented Dahua endpoint, channel starts at 1 and subtype 0 selects the main stream; subtype 1 selects the first extra stream. Confirm these values for camera versus recorder.
Decide whether the source is the camera itself or an NVR channel. Use the recorder address and recorder account for a recorder-provided stream, and check its channel numbering separately.
Copy the RTSP path from the documentation for the exact product family. Keep the address, service port, channel and main/substream selector as separate values during diagnosis.
rtsp://192.0.2.10:554/cam/realmonitor?channel=1&subtype=0What to verify
Test one camera and one stream before opening a larger camera wall. Keep the camera settings unchanged while you establish whether the first live image is stable.
Sources and scope
AeoCam is available for Windows. Camera settings below describe protocol preparation, not a certification of a particular camera or a promise of every feature in every app version. Check the installed build and the Microsoft Store listing for current availability.
Vendor documents describe the camera or protocol. No physical-camera compatibility test is claimed here. Menus and capabilities can change with model and firmware.