We have performed a calculation on the quantum transport through a qua
ntum dot pillar with hard-wall confinement, taking into account the Co
ulomb interaction in the dot as well as the exact sample geometry. We
have investigated the case of N less than or equal to 4 electrons in t
he dot. The many-particle eigensolutions in the dot, the tunnelling ra
te associated to each many-particle eigenstate in the dot, the tunnell
ing current and the corresponding conductance in both the nonlinear an
d the linear response regimes are calculated rigorously. Besides other
interesting results beyond the orthodox theory, we found that for an
experimentally accessible sample, the influence of the Coulomb interac
tion on certain matrix elements is small and can be neglected. Such an
approximation will simplify the numerical study of other physical pro
perties of the quantum dot.