This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition, when the waveguide device under analysis has physical symmetry, is used very commonly to speed up the computation time in general waveguide solvers by exploiting the symmetries of the excitation. This contribution is focused on extending its use in general problems having this type of boundary condition in the lateral and transverse walls, applying the mode-matching method. The formulation will be applied to classical waveguide devices surrounded by perfect magnetic walls, but also to simulate radiating problems. The simulation results will be compared with those obtained by other numerical techniques (based on different solvers) to test the validity of the presented formulation.