Please attempt the following solutions in order;
Your ISP or national firewall may be filtering out OpenVPN packets on UDP (port 2049). Connect to one of the TCP mode servers (right click the Purhchase-VPN tray icon and select a server which ends with ‘TCP mode’). The ‘TCP mode’ servers use port 443 which is very unlikely to be blocked as it a standard port used for secure web services.
Your router or a software firewall on your PC may be filtering connections on port 2049. Temporarily disable your firewall to check if your firewall is blocking the traffic. Some customers have found it necessary to completely uninstall the firewall software followed by connecting and reinstallation.
In rare cases the windows firewall may be blocking access to the openvpn.exe binary. Whitelist (add it to the “Exceptions” list) it for OpenVPN to work.
If the above solutions do not work then it is likely that you are located on a network which is blocking access to our VPN servers.