Have a network running 64-bit Windows OS (Windows XP Pro x64 v2003 sp1). Used Visual Studio 2005 to build a 64 bit version of a known-good sample cluster code. Downloaded and installed MPICH2 Win64 IA64. The nodes contain AMD Athlon 64x2 dual core processor 4200+ running at 2.21ghz.There are 4gb RAM. Running the sample code gives the following access error message: C:\Program_Files\MPI_Examples>C:\Program_Files\MPICH2x64\bin\mpiexec -exitcodes -n 1 -pwdfile Options.txt First_Example
Credentials for \162.18.198.244\Config rejected connecting to daycluster
Aborting: Unable to connect to daycluster
Credentials are stored in Options.txt: \162.18.198.244\Config
Aero2006 It seems like MPICH2 is trying to log in but is being rejected. The nodes are configured in the same way as are the 32-bit nodes on another network. This process works fine there. Would appreciate any insights you can offer.  Thanks, Peter