I'm about to build the Makefile for Parallel::MPI::Simple. If you find you cannot build this module, or that the tests fail, you may be on an odd system where you need to do more than pass -lmpi to your C compiler to build MPI applications. If this is the case, rerun perl Makefile.PL with appropriate LDFLAGS= and CCFLAGS= arguments. Also, this module is very new so if you manage to get it working on one of the systems not listed in INSTALL I'd love to hear about it. Checking if your kit is complete... Looks good Note (probably harmless): No library found for -lmpi Writing Makefile for Parallel::MPI::Simple Microsoft (R) Program Maintenance Utility Version 6.00.8168.0 Copyright (C) Microsoft Corp 1988-1998. All rights reserved. cp ic.pl blib\lib\Parallel\MPI\ic.pl cp Simple.pm blib\lib\Parallel\MPI\Simple.pm C:\cpanrun\build\5-10-0\bin\perl.exe C:\cpanrun\build\5-10-0\lib\ExtUtils\xsubpp -typemap C:\cpanrun\build\5-10-0\lib\ExtUtils\typemap Simple.xs > Simple.xsc && C:\cpanrun\build\5-10-0\bin\perl.exe -MExtUtils::Command -e mv Simple.xsc Simple.c cl -c -nologo -GF -W3 -MD -Zi -DNDEBUG -O1 -DWIN32 -D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT -DUSE_SITECUSTOMIZE -DPRIVLIB_LAST_IN_INC -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX -MD -Zi -DNDEBUG -O1 -DVERSION=\"0.03\" -DXS_VERSION=\"0.03\" "-IC:\cpanrun\build\5-10-0\lib\CORE" Simple.c Simple.c Simple.xs(8) : fatal error C1083: Cannot open include file: 'mpi.h': No such file or directory NMAKE : fatal error U1077: 'cl' : return code '0x2' Stop.