Trying to remove dry-erase marker from a fridge. I've tried and failed with ammonia, wd40, olive oil, comet, vinegar, old hydrogen peroxide (could be broken down/too old), dish soap and water.
Baking soda with a little water scrubbed finally worked! Came off immediately and easily as I worked it across the surface. Toothpaste (aqua-fresh) worked okay but the baking soda has been by-far the easiest.
Following up the baking soda with a whitening toothpaste (think it was Sensodyne whitening) cleaned and restored it to the original condition. Took a little while, scrubbed over with the baking soda until most of it was gone or faded. Wiped it down with soap and water then followed up with the toothpaste to finish the remaining residue and hard to reach spots.