Remote VAC Install / Archive Exports

Enterprise Vault 904.

I'm working through the process of enabling our Messaging Provisioning group to be able to export Vault archives to a PST. Using Authorization Manager, I've assigned them the "PST Administrator" role.

When I right-click Archives and select "Export", it eventually times out with..."An error occurred while getting the list of aborted Exports. Check that the Vault Directory Service is running and the computer is reachable on the network. Error: The RPC server is unavailable."

When I installed EV on this server, all I chose was Administration Console. Do I also need to install Enterprise Vault Services?

Thanks for any insight.