To pair the remote control:
Click the lock and enter your Administrator password if necessary.
Use button “Pair”
Point the remote at the infrared sensor on the front of your Mac (about 3 or 4 inches away).
Press and hold the Menu and Next/Fast-forward buttons simultaneously on the remote for 5 seconds.
Your Apple Remote is now paired with your computer. You should see a chain-link style lock appear in the center of your screen for a moment.