How to use it Paste an error code or part of the message into the box, such as 0x80070002 or 5.7.1, and pick a result to see what it means and how to fix it.
VPN error 809: the VPN server isn't responding
Likely causes
- UDP ports 500 or 4500 are blocked by a firewall, router or NAT device.
- The network you're on (hotel, guest Wi-Fi) blocks VPN traffic.
- The VPN server is down or unreachable.
How to fix it
- Try a different network, such as a phone hotspot. If it connects there, the first network is blocking VPN traffic.
- Check that the VPN server address in the connection profile is correct.
- Admins: make sure UDP 500 and 4500 are allowed through every firewall and NAT device between clients and the VPN server.
- Admins: check the RasClient events in the client’s Application log for more detail.
Checked against: learn.microsoft.com