NETGEAR Nighthawk RS300 Wi-Fi 7 router VPN client or server will not connect

The checks in more detail

If the VPN connects but is slow, test without it to see the plain speed, then try a different server or protocol such as WireGuard, which is lighter than older ones. A router's QoS or Armor feature can slow VPN traffic, so turn it off for a test. If you want to reach home from outside, check what the RS300 offers. NETGEAR routers can include OpenVPN or other remote access features, and the setup needs a public address on the internet port; a provider that shares one address between customers blocks inbound connections, which looks like a VPN fault.

Check the router's WAN address, and if it is a private one, ask the provider. Also check dynamic DNS if your address changes. A double NAT, with another router in front, needs the front device to forward the port. Keep the router's clock correct, since certificates fail on a wrong date. If a VPN drops at regular intervals, a lease renewal or a Wi-Fi roam may be the cause, so test on Ethernet. As NETGEAR community posts note for the RS300, heavy features can add load, and the router may restart under strain, so disable extra features while testing.

Keep firmware current after reading release notes. If you are using a VPN on the router itself, remember that the router's processor limits the speed, so a gigabit plan may not reach full speed through an encrypted tunnel, and the figure from a laptop running its own VPN client is often higher. Compare the two before deciding the router is at fault. Keep a note of the VPN's own settings, such as the protocol, the server and the port, because a provider's support team asks for them. Never expose management pages to the internet, and use a strong admin password on the router.