https://community.intel.com/t5/Intel-MPI-Library/Linking-MPICH2-with-MKL/m-p/781860#M390 Hi Martin,<BR /><BR />Looks you have code compiled for different platforms.<BR />If you compile your application for Intel64 architecture you need to link with mkl_blacs_mpich2_lp64.lib.<BR />32-bit version of of the mkl_blacs_mpich2.lib contains names with underscore and that's OK.<BR /><BR />BTW: mpich2 should be compiled for the same architecture.<BR /><BR />Regards!<BR /> Dmitry<BR /> Fri, 18 Mar 2011 12:23:15 GMT Dmitry_K_Intel2 2011-03-18T12:23:15Z https://community.intel.com/t5/Intel-MPI-Library/Linking-MPICH2-with-MKL/m-p/781859#M389 Hi,<BR /><BR />in addition to the thread available under <A href="http://software.intel.com/en-us/forums/showthread.php?t=66299&amp;p=1#144543" target="_blank">http://software.intel.com/en-us/forums/showthread.php?t=66299&amp;p=1#144543</A>, I have a problem linking MPICH2 and MKL with my Visual Studio 2008 project (Intel Fortran 11 compiler).<BR />I link a number of libraries to my project - if I do that without /assume:underscore, I get a whole lot of linker errors about unresolved symbols, whose names all start with an underscore (but don't end with one).<BR /><BR />error LNK2001: unresolved symbol "_MPI_Allreduce". mkl_blacs_mpich2.lib(dgsum2d_.oo) <BR /><BR />If I use /assume:underscore, however, all the imported symbols are fine, but I get linker errors in the object file of my program. The unresolved symbols here start and end with an underscore.<BR /><BR />error LNK2001: unresolved symbol "_MPI_NULL_COPY_FN_". test.obj <BR /><BR />From what I understood there are two calling conventions here. Is there a way to fix this problem without using other libraries?<BR /><BR />Martin Tue, 15 Mar 2011 14:57:55 GMT https://community.intel.com/t5/Intel-MPI-Library/Linking-MPICH2-with-MKL/m-p/781859#M389 mamey4 2011-03-15T14:57:55Z https://community.intel.com/t5/Intel-MPI-Library/Linking-MPICH2-with-MKL/m-p/781860#M390 Hi Martin,<BR /><BR />Looks you have code compiled for different platforms.<BR />If you compile your application for Intel64 architecture you need to link with mkl_blacs_mpich2_lp64.lib.<BR />32-bit version of of the mkl_blacs_mpich2.lib contains names with underscore and that's OK.<BR /><BR />BTW: mpich2 should be compiled for the same architecture.<BR /><BR />Regards!<BR /> Dmitry<BR /> Fri, 18 Mar 2011 12:23:15 GMT https://community.intel.com/t5/Intel-MPI-Library/Linking-MPICH2-with-MKL/m-p/781860#M390 Dmitry_K_Intel2 2011-03-18T12:23:15Z