The iteration method for solving the free-boundary magnetic surface equation with conducting shells has been generalized to the case of infinite region with external currents and without conducting shells. In order to do this a coordinate transformation of the form x′=x/(1+x) is carried out which enables to get a sufficient accuracy inthe region of plasmas while the meshes in the region of vacuum would not be increased. After restricting the radial region of the plasma currents the iteraction series described in [1] can be used to find the equilibrium solution of magnetic surface equation. The numerical solution of this equation in one dimension is obtained and compared with the result obtained analytically. The method described above can effectively be used in cases of two-dimension without difficulties.