Remove the product dispenser from the washing machine. Rinse the dispenser under hot running water, scrubbing away any detergent or fabric softener residue with a soft-bristled brush such as an old toothbrush. Replace the dispenser.
Add 2 cups of white vinegar or 1 cup of liquid bleach to the empty washing machine. Run the washer on the hottest setting. If your washer has a built-in cleaning cycle, follow the manufacturer's instructions and add the bleach or vinegar when prompted.
Open the washer when the cycle is finished, and wipe out the interior with a clean, dry towel.
Spot-clean any remaining residue with a mild all-purpose cleaner. Spray the residue with cleaner and wipe away any residue with a soft cloth or sponge. Rinse the washer tub with a clean, damp cloth.