ERROR: "The L2TP-VPN server did not respond. Try reconnecting. If the problem continues, verify your settings and contact your Administrator"
If you get the error message mentioned above, then check the following:
- The IPSec shared secret is wrong. Please ensure that you enter this key exactly as shown in the Server Addresses Knowledgebase article; That it's the key for the server you try to connect to, that it's in the correct case, and that there are no whitespace characters before or after (common when copy/pasting).
This by far the most common reason for this error. - Check so the connection to the VPN server isn't blocked. You need to configure your router to allow VPN passthrough or speak to your network administrator. Most modern home routers allow VPN passthrough by default so in most cases this shouldn't be the problem, but it can be if you have an advanced router or are connecting from a Corporate or University network. It can also happen in public places, such as Hotels, or in some types of Networks, such as cellular networks, depending on the provider. Another reason is if you are in a country with a restrictive national firewall.
