If not already done so, enter your dialing rules and location information in the telephone-/modem options (Windows Control Panel). Enter the connection information (IP-address, port, LAN-TAPI-password) in the LAN-TAPI-driver's settings.
On the PBX's menu check or otherwise change the LAN-TAPI-settings (IP-address, port, LAN-TAPI-password) according to the driver's settings.
Make sure that any necessary dongle licenses were purchased and also create a list of LAN-TAPI subscribers in the PBX's LAN-TAPI-settings.
Deactivate the RAS-service in your server's admintrative tools and reboot the machine. After the reboot restart the server's telephony service.
Run the Windows dialer and set the subscriber you want to test in the options.
Enter a destination number and dial.