Common errors during activation, and their meaning:

Fault 9000: 'twisted.internet.error.TimeoutError: User timeout caused connection failure.
In most cases this problem is caused by an inability of the OpenVPN Access Server installation to reach the Internet for an online activation. Please verify that Internet access is possible from this Access Server and that the DNS settings are correct. Verify on the command line that you can ping and reach Internet addresses from the operating system that the OpenVPN Access Server is installed on. Check that any firewalls or security groups are not blocking access. If your system is intentionally cut off from the Internet or if it is not possible to resolve this problem, request or perform an offline activation. In rare cases this error can also show up if the license key has already been used before for activation - all license keys are single-activation keys only. In such a case request a license key reissue.

Fault 9000: "twisted.internet.error.DNSLookupError: DNS lookup failed: address 'licensing.openvpn.net' not found: [Errno -2] Name or service not known."
This error is almost always due to a DNS resolver misconfiguration or a country-related block on your DNS servers. Please verify that Internet access is possible from this Access Server and that the DNS settings are correct. Verify on the command line that you can ping and reach Internet addresses from the operating system that the OpenVPN Access Server is installed on. Check that any firewalls or security groups are not blocking access. If your system is intentionally cut off from the Internet or if it is not possible to resolve this problem, request or perform an offline activation.

There is more information and troubleshooting steps available on our troubleshooting problems with software licensing page.