  We present an update on our calculation of the short-distance $D^0$-meson
mixing hadronic matrix elements. The analysis is performed on the MILC
collaboration's $N_f=2+1$ asqtad configurations. We use asqtad light valence
quarks and the Sheikoleslami-Wohlert action with the Fermilab interpretation
for the valence charm quark. SU(3), partially quenched, rooted, staggered
heavy-meson chiral perturbation theory is used to extrapolate to the
chiral-continuum limit. Systematic errors arising from the chiral-continuum
extrapolation, heavy-quark discretization, and quark-mass uncertainties are
folded into the statistical errors from the chiral-continuum fits with methods
of Bayesian inference. A preliminary error budget for all five operators is
presented.
