  The cross-section of (quasi-)elastic large-angle electron-positron scattering
at high energies is calculated. Radiative corrections of the orders O(\alpha^2
L^2) and O(\alpha^2 L), besides pure two-loop box contributions, are explicitly
calculated. In the second order we considered the following sources of
corrections: 1) Virtual photonic corrections coming from squares of 1-loop
level amplitudes and their relevant interferences (vertex-type and box-type
Feynman diagrams). 2) Double soft photon emission and one-loop corrections to
single soft photon emission. The results are presented in an analytical form.
