The "program cannot display the webpage" error is seen in the Monitors tab when exporting the logs from SEPM remote console accessed using a public IP (via NAT).
The "program cannot display the webpage" after clicking on export in the Monitors - Logs tab.
When exporting logs, SEPM first generates a .CSV file in a temp folder, then returns the file address to the console to save the file. In a NAT environment, for example, external IP was 10.200.x.x and internal IP is 192.168.1.x, the returned URL would be https://192.168.1.x:8445/ - the SEPM remote console cannot access this URL and cannot get the external IP address and the page shows the error "program cannot display the webpage".
This is working as per the design. SEPM cannot fully support NAT.