Hi, Is there any reason for using such an old version of MPICH? I'd suggest you try with our most recent release. Antonio On Wednesday, August 07, 2013 05:53:08 PM Alen Arturo Dioses Avellaneda wrote: Good Evening: I am trying to install MPICH-1.2.7p1 and I got a problem. I am sending the m.txt file and c.txt file. I am using CentOS5.9. I hope you can help me with this problem. I am trying to use mpich to use 2 processors I am not trying to work with nodes Alen Arturo Dioses Avellaneda Meteorological Student