Sony PCG-SRX99 - Manual (Page 144)

Troubleshooting the Mouse and Touchpad
My mouse does not work.
 Make sure the mouse is securely plugged into the USB port. See Connecting a USB Mouse for more information.
 If you are still experiencing problems, use your supplied Application Recovery CD to reinstall the mouse drivers. See
Using the Application Recovery CD(s) for more information.
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