Wipe the loose dirt or residue from the painted seals using a damp rag. A paint-thinning solvent will need to be applied to a smooth, even surface for the most effective results.
Scrub the offending paint form the seals using a scouring pad soaked in warm water. Latex paint has become the most popular household paint on the market, and can be removed with water alone if applied within the last 2 to 3 weeks; it is water-soluble and comes loose rather quickly as long as it has not cured.
Dampen a rag with acetone, which can be found in common nail polish removers. Wipe the affected window seals until the paint begins to thin; this household remedy, along with isopropyl alcohol, can safely remove small quantities of paint from plastic and rubber surfaces.
Protect your skin against alkaline burns by wearing a pair of solvent-resistant rubber gloves. Paint thinner is extremely effective on stubborn, dried paint but can be hazardous to the skin. Use this method on especially difficult oil-based paints, but make sure the solvent is suitable for the targeted surface.
Test the paint thinner on a small section of the window seal to make sure it does not eat through the surface. Apply it sparingly using a small brush or aerosol spray can, depending on your chosen application.
Wipe the paint from the seal using a dry rag and rinse the excess with water. Clean the seals with a wet sponge to eliminate any remaining paint thinner and allow them to air dry.