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.

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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
				

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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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