The electrical properties of polycrystalline CuInS2 thin films grown by coevaporation are investigated by lateral electrical conductivity measurements. It is shown that annealing of Cu-poor films in S atmosphere during an extended cool-down period enhances the lateral conductivity at room temperature. Conductivity enhancement is also observed for films annealed in an oxidizing environment. Both S and O annealing is interpreted in terms of saturation of chalcogen vacancies acting as compensating donor sites. The influence of the cool-down step on the electronic film properties is depicted by an improval of solar cell parameters of CuInS2/CdS/ZnO devices.