The original COMM.DRV still exists, and if a Win 3.1 app opens a COM
   port through this device, TAPI won't try to open it. You won't have
   any of the TAPI benefits with this app, and you'll have to manually
   configure its dialing properties, manually close it so other TAPI apps
   can use the modem, etc...
   
   Non-standard COMM.DRV replacements usually won't interfere with TAPI,
   because TAPI does not refer to this device at all. In fact, there are
   separate VxDs and SERIALXX.DLL files (and the TAPI.DLLs of course) for
   32-bit access to COM ports. The non-standard driver better not be
   calling un-supported stuff in Win95 though.
   
   In general, try to avoid Win 3.1 modem apps. As much as I lay the crap
   on WinFax Pro 7.0, for example, it's a far better solution than WinFax
   Pro 4.0 for Win 3.1. Hold out as long as practical for Win95 voice
   mail apps too, so there's no argument between non-standard apps trying
   to use the modem and conflicting with TAPI. Win95's supposed to make
   using modems easier, and Win 3.1 modem apps don't help at all.

     * 5.11.1. My Win 3.1 modem app claims to use TAPI. Will it work with
       Win95? 
       
   I haven't seen a 16-bit TAPI app yet. Apparently they exist, because
   one reader wrote about it.
   
   There are references in the Win95 resource kit to 16-bit TAPI
   programs, and the 16-bit TAPI.DLL and TELEPHON.INI files. I gather
   that they will work as long as they use this interface to communicate
   with the modem. Like Win95 TAPI apps, if this Win 3.1 app has an
   auto-answer function, it should "nicely" give up the modem when you
   try to use it for other connections, like Dial-up Networking. You also
   don't need to specify the COM port where the modem lives; only its
   name from the list of installed modems.
   
   This one reader's app comes with a version of TAPI designed for Win
   3.1, and it seems to interfere with Win95's Unimodem TAPI service.
   Microsoft documented in KB articles Q120221 and Q150280, how
   to edit or rebuild the TELEPHON.INI file, and how to enable the
   Telephony control panel. In particular, the Telephony control panel
   can remove 16-bit TAPI providers from your system, allowing 16-bit
   TAPI apps to use the 32-bit Unimodem Service Provider.