Err Msg: Ring 0 Systems. Virtual 16550 Driver...

• Microsoft Windows operating system versions 3.1, 3.11
• Microsoft Windows for Workgroups versions 3.1, 3.11
• Microsoft Windows 95

SYMPTOMS

You receive the following error message when you start Windows:

   Ring 0 Systems. Virtual 16550 Driver
   Board was not found in computer. Virtual 16550 & communication
   buffering in the DOS box will not work. It may cause lost bytes
   during the data transfer and other problems with communication
   software running under V86 DOS

CAUSE

This error occurs when you:

• Move your modem to another serial port without reconfiguring the driver.

  -or-

• Remove the modem from the computer but do not remove the corresponding Digicom Systems Incorporated (DSI) device driver (r0dsicom.drv). This device driver replaces COMM.DRV as the Windows serial communications driver and displays the error message noted above when it doesn't find the modem.

   Boca Sound Expression 14.4 VSP
   Cardinal Technologies MVP144DSP
   DSI Connection Series
   PC Logic FAX144DM

WORKAROUND

• If you move the modem to another serial port, run the DSI.EXE program included with the modem to reconfigure the adapter. Contact DSI for more information and assistance.
• If the modem has been removed, the DSI drivers should be replaced with the default Windows drivers to remove the error message.

  The DSI setup program makes the following changes in the [boot] section of the SYSTEM.INI file:

        COMM.DRV=r0dsicom.drv
  

  To replace this DSI driver, change this line to read as follows:

        COMM.DRV=COMM.DRV
  

  The following changes are made to the [386Enh] section of the SYSTEM.INI file by the DSI setup program:

        DEVICE= r0dsivcd.386
        DEVICE= r0dsibuf.386
        DEVICE= r0dsimgr.386
  

  Remark out or remove the above three lines and add the following to the [386Enh] section:

        DEVICE=*VCD
        DEVICE=*combuff
  

  NOTE: The Connection Series modems require the drivers outlined above for full functionality. You should not replace the DSI drivers listed above unless the DSI modem is removed from the system. Contact DSI for more information.

MORE INFORMATION

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