In general, the Administration Tool and the Virtual DataPort server have to be of the same major version. E.g. you cannot connect to Virtual DataPort 7.0 from an Administration Tool of version 6.0, nor vice versa. In order to connect to Virtual DataPort server 7.0, I will use Virtual DataPort 7.0 Client Tool. For more details, you can refer to [Backward Compatibility Between the Virtual DataPort Server and Its Clients](https://community.denodo.com/docs/html/browse/latest/vdp/administration/appendix/backward_compatibility_between_server_and_clients/backward_compatibility_between_server_and_clients#backward-compatibility-between-the-virtual-dataport-server-and-its-clients) section of the Virtual DataPort Administration Guide.
If you are a valid support user, you can download the Virtual DataPort Client Tool 7.0" from the [Denodo Support Site](https://support.denodo.com/resources/installer/list/Denodo%207.0#) by navigating Downloads > Installer > Denodo 7.0.
Hope this helps!