Campbell Scientific COM320 Voice Communications Modem - Manual (Page 36)

Appendix B. Updating and Configuring the COM320
4) After some delay, your computer should show a dialog similar to that
shown below. Since the driver is obtained from Campbell Scientific, you
should select the option No, not this time in the dialog.
5) After pressing the Next button, you will need to specify that the driver
be installed from a specific location as shown below:
B-2