Two issues have been identified in the measurement of the differential branching fraction of B 0 → K * (892) 0 µ + µ -decays presented in ref. [1].Both of these issues involve the calculation of the ratio of efficiencies between the decay B 0 → J/ψ K * (892) 0 (normalisation mode) and the decay B 0 → K * (892) 0 µ + µ -(signal mode), denoted as R in eq.(7.1) of ref. [1].What follows is a brief description of the nature of these problems, followed by the corrected results.To save computing resources, simulated events are only propagated through the full simulation of the LHCb detector if all charged final state decay products of the B 0 meson are within the geometrical acceptance, defined to be 10 < θ < 400 mrad in the polar angle between the particle trajectory and the z-axis.Additional loose kinematic criteria are also applied to the B 0 meson and its decay products such that the B 0 meson has p T > 1.5 GeV/c, the muons have p > 2 GeV/c and the mesons p > 0.8 GeV/c.The efficiency for these requirements is estimated from dedicated simulated samples with the requirements omitted, and which are not propagated through the detector simulation.The first mistake involved the calculation of the efficiency of these criteria which meant that the effect of the momentum cuts on the B 0 and final state products was only accounted for in the signal decay but not the normalisation decay.This has now been corrected, leading to a decrease of the differential branching fraction by a multiplicative factor of 0.97 in each q 2 bin.The factor R involves calculating the reconstruction and selection efficiencies of the signal and normalisation processes in two different regions of invariant masses of the K + π -system (m Kπ ).These regions are 644 < m Kπ < 1200 MeV/c 2 for the signal and Open Access,