  We investigate the effect of electron-electron interactions on the transport
properties of disordered quasi one-dimensional quantum wires with two or more
subbands occupied. We apply two alternative methods to solve the logarithmic
divergent problem, namely the parquet graph theory and a renormalization group
calculation. We solve the group equations analytically in the weak coupling
limit and find a power-law for the temperature dependent conductivity of a
multi-channel system. The exponent is roughly equal to the inverse of the
number of the occupied subbands.
