Why are my dishes coming out spotted or filmed, and how can I fix it?

Spotting and filming are commonly caused by hard water, low water temperature, or insufficient rinse aid. Make sure the rinse aid dispenser is filled and that water entering the dishwasher is at least 120°F (49°C). For occasional use, you can run a white vinegar rinse by placing 2 cups (473 mL) of white vinegar in a glass measuring cup on the bottom rack and running a complete wash cycle without detergent using an air-dry option. (Page 19)