How long do you heat a 17 pound cooked ham?

A precooked ham does not need to be heated. You could still heat it if you wanted to, and this is how you would do it:

For a 17-pound pre-cooked ham, preheat your oven to 325 degrees Fahrenheit. After preheating, place the ham in a baking pan or roasting pan. Cover the ham with aluminum foil and let it heat up in the oven. For a 17 pound ham, you should heat the ham for 10 to 12 minutes per pound, so it should take about 3 hours to heat up all the way through. Use a meat thermometer to ensure the ham has reached an internal temperature of 140 degrees Fahrenheit before serving.

Remember, these times are just estimates and may vary depending on your specific oven and ham. It's important to use a meat thermometer to ensure the ham is cooked to the proper internal temperature before serving.