"initialize successfully, found 7 TAPI devices". While there are only 3 devices in the drop down box.

Fristly i want to mention the "line device" concept.
line device---A physical channel composed of a telephone line and the
hardware to control it such as a fax board, a modem, or an ISDN card. The simplest kind of line device corresponds to exactly one telephone line.

In win98, the line device only mean the telephone device such as fax board, modem, ISDN card and so on. But in Win2k/xp the intension of the"line device" has been expanded.

In Win2k/xp the "line device"(in TAPI3.0 name Address Object) mean
An address represents a location on a network. The local assignment of an address to a line or channel typically takes place during the installation of the service provider but can be modified later.

So when you enum the lines device in win2k/XP , you will get your modems device , also some other devices such as "IPCONF line", "H323 line","RAS VPN line" ..and so on.

Since our component is working with the modem devices mainly, not other devices("IPCONF line", "H323 line"...), so the very DEMOs have a filter code when adding the devices name to the combobox.

For example, the "Predictive Dialer" demo

Private Sub Form_Load()
 Dim line As ITAPILine
 Set mTapiex = New TAPIEx
 mTapiex.Initialize   'Initialize
  For Each line In mTapiex.Lines  'enumerate the line evices**
    If line.Caps.Line_Features And LINE_FEATURE_MAKECALL > 0  Then
       CbLines.AddItem line.DeviceName
    End If
End Sub
"If line.Caps.Line_Features And LINE_FEATURE_MAKECALL > 0 Then" only add the devices which support makecall function

So now you understand why "It saind "initialize successfully, found 7 TAPI devices". While there are only 3 devices in the drop down combo box. I know I have not installed that many TAPI devices.