An operator of the permittivity can completely describe alone a microwave response of conductors with the spatial dispersion. A wave problem is formulated to search the eigenvalues of the permittivity operator, similar to the problem of the wave propagation in hollow waveguides and resonators, but non-self conjugated. Dispersion relations and general solutions are obtained. A significant role of the spatial-type force resonances is considered. Due to the self-consistency of a kinetics problem, the spatialtype force resonances are added to and usually dominate over the influence of boundary conditions. The obtained resonances include particular solutions corresponding to the surface impedances for the anomalous skin effect, for superconductors, as well as four novel solutions. The general frequency dependence of the surface impedance is derived for all solutions except that for a superconductor.