The stability of a plane, premixed flame is re-examined for finite activation energies. This stability problem must be solved numerically; however, the calculations are performed in the spirit of the infinite activation energy theory. Numerical difficulties in determining the steady solution for both adiabatic and non-adiabatic flames are identified and resolved. The stability equations are solved using the compound matrix method. The theory and calculations presented resolve all discrepancies between the infinite activation energy results and numerical calculations reported previously.