To remove adhesive from glass, begin by scraping the glass with a single edge razor, suggests This Old House. Follow up with a spray household cleaner, or apply a product specially designed for removing adhesive from glass surfaces such as Lift Off, Goo Gone or Unstick.
Adhesive removers are readily available in home improvement centers, picture-framing shops and hardware stores. They usually get rid of adhesive residue in only one or two applications. Lacquer thinner is another option for hard-to-remove sticky substances. Because it is flammable, remember to use lacquer thinner in a well-ventilated area, and wear appropriate protection such as gloves, goggles and a respirator.