Fill a bucket with hot water. Add a squirt of dish soap and mix it up well.
Scrub the inside edges of the door of the dishwasher with an old toothbrush and the soapy water. Scrub in the crevices and grooves of the rubber seal, around the hinges and along the bottom of the door.
Wipe off the loosened debris with a sponge and soapy water. Wipe down the interior surface of the door. Use the sponge to also wipe around the drain area at the bottom of the dishwasher. Go over these areas with a damp rag to remove loosened debris.
Pour 2 cups white vinegar into the bottom of the dishwasher. Turn the machine on the hottest water cycle.
Let the dishwasher run through about half the cycle. Stop the dishwasher midway through the wash and let it sit for 20 minutes so the vinegar can work.
Run the rest of the wash cycle. Wipe out the inside of the dishwasher with a dry rag to remove any remaining debris.