After you install or upgrade to Windows 2000 or Windows XP on a laptop computer with a port replicator or docking station, the mouse pointer may jump or behave erratically.

The touchpad or "nub" pointing device on some laptop computers uses a 3-byte packet. The Microsoft IntelliMouse uses a 4-byte packet (the extra byte is for the wheel). When you use both at the same time, the BIOS in some computers may interpret the packet string incorrectly. The erratic behavior occurs when the fourth byte of the first packet is mistaken for the first byte of the second packet, and so on.

To resolve this issue, use any of the following methods:

• Check with the manufacturer of the laptop computer for an updated BIOS.
• Use a two-button mouse.
• Connect the wheel mouse to the laptop computer with a serial-to-PS2 port converter.
• If the mouse and laptop support it, connect the mouse to the USB port.

This behavior is by design.