In a recent paper we have given the macroscopic and microscopic description of the generating solution of toroidally compactified string theory BPS black holes. In this note we compute its corresponding microscopic entropy. Since by definition the generating solution is the most general solution modulo U-duality transformations, this result accounts for the degeneracy of microstates determining the entropy of any regular BPS black holes of toroidally compactified string (or M) theory.