The Albaani Site

Someone came in and gave salām to the Shaikh and said, “كل عام وأنتم بخير” [“May you be well every year,” etc., this is said in Arabic speaking countries on Eid] so he said, “This addition has no basis, it is enough for you to say, ‘May Allaah the Most High accept [our deeds] …,’ ‘كل عام وأنتم بخير’ [‘May you be well/blessed every year,’]—this is a greeting of the disbelievers which came to us Muslims due to our heedlessness, ‘And remind, for reminders benefit the believers.’” [51:55]
Al-Hudā wan-Nūr, 323.