The Main database is on a Windows Server - physically on the server OR hosted by Filemaker or Filemaker Server? Can you connect with the hosted? database over the network? What version of Windows Server? 2003? 2007?
What VPN is being used? Have you connected to a server and viewed files with the VPN client?
What is your operating system and version? What version of Filemaker v11? v11.03?
Concise and complete information will help get a response.;..