Use the following steps to enable your PC-Telefon to work with the Windows XP default Firewall protection:

1. Select Network Connections from your Windows Control Panel:

2. Select the connection you use to access Internet from Dial-up or LAN list:

3. Select the Advanced property sheet.

4. Here you can disable the Internet Connection Firewall and exit with OK button or click on Settings button to enable the ports.

5. Click on Add button to enable the PC-Telefon UDP and TCP ports.

5.1 Enter the description of service (PC-Telefon UDP), IP address (localhost), port numbers (9084) and select UDP protocol:

5.2 Add new service settings and enter the description of service (PC-Telefon TCP), IP address (localhost), port numbers (9084) and select TCP protocol:

6. Check the PC-Telefon UDP and TCP services and exit with OK button.

Now, you will hear the welcome message when you dial to pctt.net (or just #) gateway.