  We have calculated the diffractive dijet cross section in low-Q^2 ep
scattering in the HERA regime. The results of the calculation in LO and NLO are
compared to recent experimental data of the H1 collaboration. We find that in
LO the calculated cross sections are in reasonable agreement with the
experimental results. In NLO, however, some of the cross sections disagree,
showing that factorization breaking occurs in that order. By suppressing the
resolved contribution by a factor of approximately three, good agreement with
all the data is found. The size of the factorization breaking effects in
diffractive dijet photoproduction agrees well with absorptive model
predictions.
