Question details:

The Connect using a dial-up modem option in the New Connection Wizard is unavailable.

Answer:

This problem can appear if the following conditions are true:

- You upgraded your computer to Microsoft Windows XP from Microsoft Windows 98.
- The following entries in the Windows registry are damaged or have incorrect settings:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Telephony\Cards\NextID

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Telephony

The solution on how to resolve this problem can be found here.