COMx not available error on Windows NT/2000

Problem:
Receiving a COMx not available error when you try to run the Software Wedge under Windows NT or Windows 2000 with a device that transmits continuous data.

Solution:
When an NT/2000 machine boots, it tries to detect serial mice. If a device is connected to a COM port and the device is transmitting data while NT is booting and looking for a serial mouse, Windows receives COM errors and disables the serial port.

To fix the problem, disable NTDETECT’s attempt to identify the serial mice on COMx:
Try adding a switch in the boot.ini file.
/NoSerialMice:COMx - Disables the detection of serial mice on COM x, where x is the number of the port.

This information was provided by Microsoft:
http://support.microsoft.com/support/kb/articles/q131/9/76.asp