Windows NT attempts to probe the serial ports on boot-up to detect any serial mice. This can cause problems with other serial devices such as UPS's.

Change the attributes for BOOT.INI so it is not 'Read Only', BOOT.INI is found in the root directory of the first partition. And open the file using Notepad or another text editor (not Microsoft Word or any word processor).

Listed under the [operating systems] section are all the OS's the NT boot loader can launch.

At the end of the each entry add '/NoSerialMice' (without the quotation marks).

The new entry should look similar to:
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00" /NoSerialMice

Changes will take place on the next reboot.

Disclaimer: Modifying the registry can cause serious problems that may require you to reinstall your operating system. We cannot guarantee that problems resulting from modifications to the registry can be solved. Use the information provided at your own risk.