We run a small business and have a server that runs our VPN on
Windows Server 2012.
Our VPN was working fine until we restarted our router and it seems that restart procedure broke the VPN. We are not sure if it is a coincidence or not. At this stage we cannot connect to the VPN from any client. (There is a file server on the same server which we can access). We receive this message:
Error 800: The remote connection was not made because the VPN tunnels failed. The VPN server might be unreachable. If this connection is attempting to use an L2TP/IPsec tunnel, the security parameters required for IPsec negotiation might not be configured properly.
On the server which we have remotely accessed, we have gone into Server Manager > Remote Access and had a look at the log and we receive multiple errors. One of which is different variations of:
Failed to apply IP Security on port VPN0-104 because of error: A certificate could not be found. Connections that use the L2TP protocol over IPSec require the installation of a machine certificate, also known as a computer certificate.. No calls will be accepted to this port.
The other error is:
The Secure Socket Tunneling Protocol service either could not read the SHA256 certificate hash from the registry or the data is invalid. To be valid, the SHA256 certificate hash must be of type REG_BINARY and 32 bytes in length. SSTP might not be able to retrieve the value from the registry due to some other system failure. The detailed error message is provided below. SSTP connections will not be accepted on this server. Correct the problem and try again. The system cannot find the file specified.
We have googled a SHA256 certificate and had a look in the registry for this file and it is not there. No one has accessed the server so is it possible that the certificate could have been deleted by itself?
Another thing we have tried is we have gone into the
Remote Access Management Console and clicked on Operational Status. We receive the following error:
An unknown system error has occurred. Check if the Remote Access Management service is running.
The resolution to this problem is:
Enable (Start-Service ramgmtsvc) or restart (Restart-Service ramgmtsvc) the service at an elevated PowerShell prompt.
As a result of seeing this error we have restarted DNS, DHCP, Remote Connection services numerous times but it has not helped. We have also restarted the entire server and this did not help either.