Troubleshooting Faxing in Windows 3.1 and Windows for Workgroups

This document addresses some solutions to issues we have found when
faxing out using different fax programs. Some of these issues include:

  *  Fax transmissions are not sent at the optimal speed - failed fax
     events
  *  WinFax is unable to communicate with the modem.


Windows 3.1 Changes

Using the WFXCOMM.DRV
If you are using Winfax Lite, the WFXCOMM.DRV is automatically
installed in your system. If you are using Winfax Pro, or any other
fax software, WFXCOMM.DRV will have to be installed manually. Below
are the steps to download and install WFXCOMM.DRV in your system:

  1.  If you do not have WFXCOMM.DRV, download it from our BBS at
      (847)982-5092 or FTP Site at ftp.usr.com.
  2.  The file you downloaded is a self extracting executable. Run 
      the executable to extract it to the directory of our 
      choice(i.e. wfxcom.exe c:\temp).
  3.  Move WFXCOMM.EXE into your Windows\System directory.
  4.  Using a text editor, edit the SYSTEM.INI file in your Windows
      directory. Change the line COMM.DRV=COMM.DRV to 
      COMM.DRV=WFXCOMM.DRV
  5.  Still in the SYSTEM.INI file, add the following text to the 
      end of the [386enh] section:

      COMxFIFO=2
      COMxBUFFER=1024
      COMxAUTOASSIGN=1
      COMxTXSIZE=14
      COMxRXSIZE=8
      COMBOOSTTIME=30

      Replace the `x'' above with the COM Port your modem is on.


Windows for Workgroups 3.11 COMM.DRV

Unlike previous versions of Windows 3.x and Windows for Workgroups
3.1, Windows for Workgroups 3.11 uses a new architecture for the COM
Port driver. The COMM.DRV in Windows for Workgroups 3.11 uses what is
known as the "VCOMM architecture".

The COMM.DRV supplied with WFW 3.11 can properly handle 16550A type
serial ports, but ONLY if additional entries are inserted into the
[386Enh] section of the Windows SYSTEM.INI file. By default, only the
receive FIFO buffer is enabled on the 16550A serial port. Without the
additional SYSTEM.INI entries, the transmit FIFO buffering capability
of the 16550A serial port will be inactive. If the transmit FIFO is
inactive, 14400bps and 9600bps fax SENDING may experience random or
frequent failures.

The following settings were determined by examining the Windows for
Workgroups 3.11 SERIAL.386 source code and verifying FIFO operations
using a hardware monitor.

Enabling FIFO support in WFW 3.11
To fully enable the FIFO capabilities of a 16550A serial port, insert
the following entries into the [386Enh] section of your Windows
SYSTEM.INI file(located in your Windows\System directory):

COMxFIFO=2    <--  This entry can be omitted, but if present, MUST
                   be set to 2 or 1, never 0.
COMxTXFIFO=1  <--  1 activates the 16 byte (non configurable) transmit
                   FIFO, default of 0 deactivates the transmit FIFO.
COMxRXTRIGGER=8  <--  Receive FIFO IRQ threshold, must be 1, 4, 8, or
                      14 (if entry is omitted, default is 8)

- `x' is the COM Port number

Note:  These entries will be ignored if:
     *  You do not have a 16550A type serial port
     *  You are not running the VCOMM version of COMM.DRV(which comes
        with Windows for Workgroups 3.11)
     *  You are using WFXCOMM.DRV(which is not compatible with Windows
        for Workgroups 3.11)

Due to the new communications driver used by Windows for Workgroups
3.11, you can not use WFXCOMM.DRV.. You should use the default
COMM.DRV file that comes with WIndows for Workgroups 3.11. The
difference, however, is that the commands to enable the transmit and
receive threshold levels are different than previous version of
Windows.

            Before                   Now
     
            COMxTXSIZE = 14          COMxTXFIFO = 1
            COMxRXSIZE = 8           COMxRXTRIGGER = 8