Disconnect the microwave oven's power source.
Open the door, and then locate the two screws on the top of the grille, located at the top of the front of the microwave. Remove the grille from the front of the microwave.
Remove the charcoal filter, if one is installed on your microwave. To remove the charcoal filter, slide the filter to the left, and then pull it toward you.
Remove the lamp cover by removing the screw securing it in place. Remove the lamp cover.
Pull the light bulb out of the light socket and discard. Insert the new light bulb into the light socket, using care to not touch the glass cover with your fingers.
Replace the light cover, charcoal filter and top grille, using the screws that you removed earlier.
Close the microwave door and then restore power to the appliance.