  The Casimir effect for Dirac as well as for scalar charged particles is
influenced by external magnetic fields. It is also influenced by finite
temperature. Here we consider the Casimir effect for a charged scalar field
under the combined influence of an external magnetic field and finite
temperature. The free energy for such a system is computed using Schwinger's
method for the calculation of the effective action in the imaginary time
formalism. We consider both the limits of strong and weak magnetic field in
which we compute the Casimir free energy and pressure.
