Dear All: With boost MPI, I trying to ask some worker nodes to send some message to the single master node. I am using OpenMPI 1.3.4. I use an array recvArray[row][column] to receive the message, which is a C++ class that contain int, member functions. But I got an error of terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::mpi::exception> >' what(): MPI_Test: MPI_ERR_TRUNCATE: message truncated[n124:126639] *** Process received signal ***[n124:126639] Signal: Aborted (6)[n124:126639] Signal code: (-6) It seems that the master cannot find enough space for the receicved message. But, I have decleared the recvArray<calssPackage> , which is a vector with element as my received class package. The error is very wierd. When I open the recvied package, the elements are not expected numbers buy only some very large or small numbers. Any help is appreciated. Jack July 2 2010 _________________________________________________________________ The New Busy is not the too busy. Combine all your e-mail accounts with Hotmail. http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4