Hi there,
Depending on your operating system e.g. windows version it could be a few problems.
Windows 98 and below - USB driver support is very limited, you will have to load a driver for the mouse which is usually with the mouse when you bought it. Alternatively you can usually find these by using the manufacturers website or simply a google search for your hardware name + driver
Windows XP - This should pickup the hardware without any problems. When inserting or removing a usb device you should hear a notification sound. If you dont hear this sound you may have a problem with the drivers for your usb ports. You should try the mouse in another computer and also another usb device e.g. printer in your laptop to verify. Again a search for drivers may help
Ben, March 2008