  A conjecture of S. Ram\'{\i}rez states that every indecomposable
non-degenerate involutive set-theoretic solution to the Yang-Baxter equation
with dihedral permutation group of order $2n$ has cardinality $2n$. The
conjecture is verified for odd $n$ and disproved for even $n$. The proof for
odd $n$ is obtained from the more general result that the permutation group of
a finite solution never acts as a Frobenius group.
