The relaxation of a nonequilibrium distribution of electrons in a mixture of CCl4 with either Ar or Ne is studied. In this paper, electron-CCl4 and electron-inert gas elastic collisions, vibrationally inelastic collisions between electrons and CCl4, as well as the electron attachment reaction with CCl4, are included in the analysis. The time dependent electron energy distribution function is determined from the Boltzmann equation and the energy relaxation times are determined. The coupling of the thermalization process and the attachment process are discussed in detail. The results from the calculations are analyzed analogous to experimental studies, and the methodology of the experimental reduction of the data is studied.