@MACH100 wrote:
I have a Nighthawk X4S D7800 router for my home broadband, with an FTTP connection to my ISP.
That is a now slightly aged (~2016) DSL modem/router. I assume that you are using it as a router, bypassing the modem bit.
Since it came out Netgear has removed various features features, usually on the grounds of security. That includes ReadyCLOUD and Remote Management.
Support for ReadyCLOUD feature ends spring 2023 | Answer | NETGEAR Support
Why is the Remote Management feature being removed from NETGEAR routers? - NETGEAR Support
Depending on what you want to do perhaps a VPN is what you want.
Manuals are always a good place to start.
Visit the support pages:
Support | NETGEAR
Feed in your model number and check the documentation for your hardware.
Check the section in the manual Use VPN to Access Your Network
