The phone sends the call information per Action URLs to the specified TCP port on your PC. The TCP port must therefore be enabled in your (Windows-) firewall. If you use a different firewall, you must configure it manually.

If the filrewall blocks incoming TCP connections, you don't get any TAPI call events.

Example configuration of Windows XP firewall for TCP port 8080:

  1. Open the firewall configuration by: [Start > Control Panel > Security Center > Windows Firewall]
  2. Select Page "Exceptions"
  3. Click to button [Port...]
  4. Enter a name, for instance: "enable TCP port 8080 for snom TAPI"
  5. Enter port number "8080" an click [OK].

Tip: Command file for automatic firewall configuration:win_firewall_cfg.cmd