  We consider the regular subgroups of the automorphism group of the linear
Hadamard code. These subgroups correspond to the regular subgroups of
$GA(r,2)$, w.t.r action on the vectors of $F_2^{r}$, where $n=2^r-1 $ is the
length of the Hamadard code. We show that the dihedral group $D_{2^{r-1}}$ is a
regular subgroup of $GA(r,2)$ only when $r=3$. Following the approach of
\cite{M} we study the regular subgroups of the Hamming code obtained from the
regular subgroups of the automorphism group of the Hadamard code of length 15.
