I am also having this problem....
I am trying to set up vpn access from a different computer. I have placed a copy of the pad file that is on the server on the remote computer.... I log in to the VPN fine and I am able to access the folder on the server where the database is located, however, when I try and open the ACT! database from the remote computer I get the same error message.
It works fine when I am in the office... It is only a problem when I try and access it from a remote location.
HELP... I have a marketing assistant starting in 2 weeks and I need to resolve this issue and gain access to the database from a remote computer.