1. Power off the system.
2. Rotate the retainer counterclockwise until it can be removed from the keyboard.
3. Separate the trackball and the retainer. Wipe off any oil or dust from the trackball, retainer and the trackball housing using a cleaner or cotton swab.
4. Assemble the trackball and retainer, then put it into the housing and rotate it clockwise until its notches are set in position.
NOTE: When cleaning, make sure not to spill or spray any liquid intothe trackball housing (keyboard or system).