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Let X be a real normed space and Y a Banach space and f:X→Y. We prove the Ulam-Hyers stability theorem for the quartic functional equation f(2x+y)+f(2x-y)-4f(x+y)-4f(x-y)-24f(x)+6f(y)=0 in restricted domains. As a consequence we consider a measure zero stability problem of the above inequality when f:R→Y.