When one connection is made through shared memory (Inter-Process Communication connection) and the other connection is made through sockets (User Datagram Protocol - UDP), the Advantage Database Server counts two user license.
Try following steps:
- open the Registry Editor
- navigate to "\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Advantage\Configuration"
- create a DWORD registry key named "ALLOW_IPC_CONNECTION" and set the value to "0