— In a proceeding pursuant to article 7 of the Real Property Tax Law, petitioners appeal from an order of the Supreme Court, Westchester County, dated May 23, 1977, which treated respondents’ motion to dismiss the petition as one for summary judgment and granted the motion. Order reversed, on the law, with $50 costs and disbursements, and motion denied. Questions are raised in the affidavits as to whether petitioners complied with subdivision 1 of section 512 of the Real Property Tax Law, whether respondents waived the possible lack of compliance, and whether petitioners were affirmatively led into believing they had complied with all prerequisites to challenging the tax assessments in issue. It was therefore error to grant respondents summary judgment (see Matter of Henderson v Silco, 36 AD2d 439; Matter of Romas v Huifcut, 39 Mise 2d 872). Suozzi, J. P., O’Connor, Gulotta and Cohalan, JJ., concur.