Previously I've already been able to connect to my server with openVPN. Now I've set up a new one with the same configuration, if I remember correctly, and on a client when trying to connect I get this:
ERROR: Cannot open TUN/TAP dev /dev/net/tun: No such device (errno=19)
Exiting due to fatal error
I run it as "sudo openvpn client.ovpn".
modprobe tun;lsmod |grep tun