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Q131976: How to Disable Detection of Devices on Serial Ports

Article: Q131976
Product(s): Microsoft Windows NT
Version(s): WinNT:3.1,3.5,3.51,4.0
Operating System(s): 
Keyword(s): kbusage
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 3.1 
- Microsoft Windows NT Workstation version 3.1 
- Microsoft Windows NT Advanced Server, version 3.1 
- Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0 
- Microsoft Windows NT Server versions 3.5, 3.51, 4.0 
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SUMMARY
=======

This article explains how to modify the Boot.ini file to disable the detection
of devices on COM ports.

When you start Windows NT, NTDETECT searches for the pointing device (usually a
mouse). In the course of this process, data is sent to the serial (COM) ports.
If a serial mouse is detected, Windows NT disables the port so a device driver
for the mouse can load instead. If a device is not detected, Windows NT disables
the port. A disabled COM port does not display any information in Control Panel
Ports.


MORE INFORMATION
================

To disable the detection of devices on COM ports in Windows NT:

1. Make a backup copy of the Boot.ini file.

2. Remove the hidden, system, and read-only attributes from the Boot.ini file.

3. Using a text editor (such as Notepad) open the Boot.ini file.

4. Add the /NoSerialMice option to the end of each entry in the [operating
  systems] section of Boot.ini. See the example below for more information.

5. Save Boot.ini and quit Notepad.

6. Restore the hidden, system, and read-only attributes to the Boot.ini file.

7. Shutdown and restart Windows NT.

The following is a sample of the Boot.ini file:

     [boot loader]
     timeout=3
     default=multi(0)disk(0)rdisk(0)partition(1)\WINNT35

     [operating systems]
     multi(0)disk(0)rdisk(0)partition(1)\WINNT35="Windows NT Workstation
        Version 3.51" /NoSerialMice

     multi(0)disk(0)rdisk(0)partition(1)\WINNT35="Windows NT Workstation
        Version 3.51 [VGA mode]" /basevideo /sos /NoSerialMice

NoSerialMice Syntax
-------------------

/NoSerialMice          - Disables the detection of serial mice on
                        all COM ports.

/NoSerialMice:COMx     - Disables the detection of serial mice on
                        COM x, where x is the number of the port.

/NoSerialMice:COMx,y,z - Disables the detection of serial mice on
                        COM x, y and z.

NOTE: The /NoSerialMice option is not case sensitive.

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Keywords          : kbusage 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT350search kbWinNT400search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTW310 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS350 kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS351search kbWinNTS350search kbWinNTS310search kbWinNT310Search kbWinNTW310Search
Version           : WinNT:3.1,3.5,3.51,4.0
Issue type        : kbhowto

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