Preheat your roaster oven to 325 degrees F.
Add the water to the bottom of the roaster oven.
Use a sharp knife to score ham diagonally, about ½ inch deep.
Wrap the ham in foil, leaving it open at the top.
Place the ham on the rack. Set the rack in the preheated roaster oven. Roast it for 1 hour and 30 minutes.
Follow the package instructions to make the glaze while the ham roasts.
Brush with half the glaze. Wrap the ham up again and roast for another 1 hour.
Brush the remaining glaze on the ham, and turn the heat to 425 degrees F. Roast for 15 minutes until the internal temperature reaches 140 degrees F on the meat thermometer.
Rest 10 minutes before serving.
