Anyone have any suggestions about how to do this? I've tried Comet, bleach and windex, all applied with plenty of elbow grease, but the stains aren't budging.
Any other ideas?
Talk to a beauty supply shop. There are commercial hairdye removers that beauty shops use. The type you need will vary with the type of dye that caused the stain. It may be helpful if you can bring the offending product with you. This is a scary thought but one site suggested using more hair dye to remove the stain. The theory being that the solvent in fresh dye will soften the old stain.