hi why im seeing this errors? im doing everything based on the manual! thanks, [mojtaba@Mojtaba mpich-3.1]# mpiexec -n 5 -f ./machinefile ./examples/cpi [mpiexec@Mojtaba] HYDU_parse_hostfile (utils/args/args.c:319): unable to open host file: ./machinefile [mpiexec@Mojtaba] mfile_fn (ui/mpich/utils.c:336): error parsing hostfile [mpiexec@Mojtaba] match_arg (utils/args/args.c:152): match handler returned error [mpiexec@Mojtaba] HYDU_parse_array (utils/args/args.c:174): argument matching returned error [mpiexec@Mojtaba] parse_args (ui/mpich/utils.c:1596): error parsing input array [mpiexec@Mojtaba] HYD_uii_mpx_get_parameters (ui/mpich/utils.c:1648): unable to parse user arguments [mpiexec@Mojtaba] main (ui/mpich/mpiexec.c:153): error parsing parameters -- Mojtaba S. Moghani Faculty of Environment University of Tehran