Is the stable tau-neutrino really an allowable cold dark matter candidate?

Considering the annihilation of massive tau-neutrinos in the Galactic Halo, we show that it is difficult to obtain concordance between the observed (directly on indirectly) and predicted fluxes of cosmic electrons and positrons in the case of a stable tau-neutrino with mass m ≈ 1–24 MeV and magnetic moment μ ∼ 10−6 μB. These results exclude the possibility for such a tau-neutrino being the dominant cold dark matter particle component.