What is the best way to remove bathroom paint from a new upvc window frame?
Bathroom paint is not designed to adhere to plastic. You should be able to peel it off without damaging the frame. In the future, if you get paint on plastic, resist the urge to wipe it up. It comes off easier if it’s a drop than a smear. If the paint is relatively new (a week or less), you can remove what’s left with water or Simple Green. Longer than that and you’ll need to use “Goof Off” (from Home Depot or Lowe’s, etc.). Rub with a rag dampened with Goof Off and as soon as the paint is removed, scrub with Simple Green to remove the Goof Off before it can soften the plastic frame.