The temperature of a baked ham should be taken at the thickest part of the ham, avoiding the bone, because the bone can give an inaccurate reading due to being colder than the meat around it. This is where the temperature will give the most accurate indication of doneness or heating status for the ham.

For a precooked ham being reheated, the internal temperature generally should reach about 140°F (60°C) for serving, but the key is to measure well into the thickest part to ensure it's heated through evenly.

In summary, insert the thermometer probe deep into the thickest part of the ham's meat, making sure it does not touch the bone for an accurate temperature measurement.