OpenVPN remote_list_error on Client


I have successfully installed OpenVPN and can log in as admin to OpenVPNAdmin with SSO. I created a new certificate in the GUI and downloaded the .ovpn file to my IOS client and opened it with the OpenVPN app, and then used it to create the profile.

In my FritzBox, I opened the UDP/1194 port and forwarded it to my device.

When I now establish a connection, I get the following error message in the client:

Connection Failed
Error message: remote_list_error: current remote server endpoint is undefined

The server address (external) is my Syncloud Domain.

What I’m doing wrong here? Any ideas?


I have done some further diagnostics and have the following information:

I have another RaspberryPi in my network with an old PIVPN (OpenVPN) installation. If I change the UDP/1194 port on the FritzBox to this server and load the profile onto my IOS device, I can establish a VPN connection without any problems.

I then changed the UDP/1194 port in the FritzBox back to my Syncloud server and then started a connection with the PIVPN profile. Of course, the connection must not be established because the certificate is wrong, but what you can see in the Syncloud OpenVPN Admin GUI in the Home tab is a connection.

Common Name	Real Address	Virtual Address	KB Received	KB Sent	Connected Since	Username	
UNDEF	Copy to clipboard	0	0	28	1717579245	
UNDEF	Copy to clipboard	0	0	42	1717579240

So from my point of view the port forwarding is OK, but still no connection can be established with the Syncloud OpenVPN profile.

I fixed the issue by changing the OpenVPN config Protocol line from udp6 to udp.


Which config file did you change?

Hi Boris,

in the OpenVPNAdmin GUI:
Configuration / OpenVPN config / Proto: udp

I think this is the server.conf file of OpenVPN:

root@syncloud:~# vi /var/snap/openvpn/current/openvpn/server.conf
proto udp