Hello, I do not understand how to solve my issue alone so I write to you. I try to install the 1.4.1p1 version of MPI on Windows 7 in 64bits but it fails during the source distribution step. The .msi and smpd.exe are running but the use of mpich2.sln is issuing. When I open mpich2.sln with Visual Studio 2010 express, it must convert files to run in the 2010 version. This operation resulted but there are many warnings (the sum up is called UpgradeLog.XML in the attachment) and some projetcs are not available (mpich2ff, MPICH2Installer, MPICH2x64Installer, mpif90, wmpiconfig, mpiexec and wmpiregister). After that, i try to build ch3sockRelease solution in mpich2 but it fails. Visual studio assistant note that several projects are obsolete (mpi - Release Win32, smpd_util - Relesae Win32, dbg -ch3sockRelease Win32, rlog -Release Win 32, pmi - Release Win32, executive - Release Win32, mpl - Release Win32, ch3nemesis - Release Win32, mpich2 - ch3sockRelease Win32). Could you help me? I don't understand what is going wrong... Thank you for your help. Good bye.