I have a new VPN 3005 running 4.0.4.a-k9. I have configured the public and private interfaces with IP addresses. However, I can only access the GUI with through the private interface. When attempting to access the public interface the web page does not load the GUI but says "Done" at the bottom. I have tried Firefox and IE but no luck either way with the public interface.
First of all we need to make sure that HTTPS access is allowed on the Public interface. For confirmation, please goto Configuration > Interfaces > Public > WebVPN and see if the 'Allow Management HTTPS sessions' is checked. You will also need to goto Administration > Certificate Management and make sure that the Public interface shows the correct IP and expiration under SSL certificates.
Please rate if it is helpful.