The UID status on the IP camera’s user interface should be “Connected” otherwise, we won’t be able to view the camera through EnViewer.
Possible reasons why UID would be “Disconnected”:
IP camera is not connected to the router and the internet. Verify connections.
IP camera is behind 2 NAT (Router behind router). Make sure the IP camera is behind the first router. Better if there is just one NAT.
The router does not support UPNP Forwarding. Verify it from manufacturer.
The router supports UPNP Forwarding but it is not enabled