Most problems with Extra Dialer, Modem Spy, Active Phone Server are because of driver. Program uses modem driver to access modem's voice features. Old drivers (or incorrectly installed new drivers) allow program to use data/fax features of modem, but not voice. So, in order to get above programs working, you should upgrade modem driver.
Also, If you are running Windows 95, you will need to upgrade Unimodem/V driver. (setup instructions)
Please note: Extra Dialer, Modem Spy and Active Phone Server work with voice modem only.