This is weird. If I chdir to /home/edscott/tmp and execute the following command I get: edscott@tauro ~/tmp $ mpiexec -n 2 -hosts tauro,velascoj /bin/hostname tauro velascoj But if I chdir to /home/edscott/temp and do the same I get: edscott@tauro ~/temp $ mpiexec -n 2 -hosts tauro,velascoj /bin/hostname tauro [mpiexec@tauro] control_cb (./pm/pmiserv/pmiserv_cb.c:202): assert (!closed) failed [mpiexec@tauro] HYDT_dmxu_poll_wait_for_event (./tools/demux/demux_poll.c:77): callback returned error status [mpiexec@tauro] HYD_pmci_wait_for_completion (./pm/pmiserv/pmiserv_pmci.c:197): error waiting for event [mpiexec@tauro] main (./ui/mpich/mpiexec.c:331): process manager error waiting for completion Wouldn't a message such as "`pwd` directory does not exist on node velascoj" be more illustrative? ------------------------------- Dr. Edscott Wilson Garcia Applied Mathematics and Computing Mexican Petroleum Institute