On 20 June 2012 05:46, Syed Ahsan Ali Bokhari wrote: >> >> Dear All, >> >> I am having following error while running an executable that was compiled using gfortran. Please guide me. >> >> [root@pmd03 bin]# ./int2lm_seq_v1.18 >> ./int2lm_seq_v1.18: error while loading shared libraries: libgfortran.so.3: wrong ELF class: ELFCLASS32 The runtime linker is finding the 32-bit version of libgfortran.so.3 but you are trying to run a 64-bit program. There are a number of ways to tell the dynamic linker how to find the right library, see http://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic