It's not uncommon for a dishwasher to develop orange stains inside. It can come from tomato-based food not being properly rinsed off and even from hard water deposits. It might take a little work, but you should be able to get your dishwasher looking like new using some common household ingredients.
Fill a bucket with warm water and add a few squirts of dish soap. Swish it around to mix.
Pull the racks out of the dishwasher so you can easily reach all interior surfaces. Dip the rag in the soapy water and clean all surfaces. Be sure to clean around the seal on the door, as well. With a wet sponge, clean the soapy solution off along with any debris.
Place the racks back in the dishwasher. Place a cup of white vinegar on the top rack and run the dishwasher through a full cycle.
Pour a packet of unsweetened lemonade drink mix into the detergent reservoir if stains remain. Run the dishwasher through another cycle. The citric acid in the mix will work to remove those mineral and iron deposits.