VPN unable to connect

I’ve configured the OpenVPN server on my Routerboard RB450G as per the instructions here:

http://daffy.za.net/2010/02/openvpn-mini-guides-mikrotik-routeros-vpn-server/

I then installed and configured the client as per the instructions here:

https://www.youtube.com/watch?v=H45ReE2JJKo

I’ve ensured port 1194 is open in the RouterOS firewall, and I’ve outright disabled the Windows Firewall on the client computer.

If I try to connect to port 1194 on the IP address of the VPN server using netcat it looks like I’m getting a handshake request, I get the following gibberish:

@���/�

However when I try to connect using the OpenVPN client it just sits there with a blank log screen. Doesn’t prompt for password, doesn’t give me any errors at all. Just says it’s unable to connect.

What am I doing wrong?