Unable to determine machine architecture. Set the environment variable FLUENT_ARCH and try again
Problem Description: When trying to launch ANSYS FLUENT 12 on AIX you receive the following error:
Unable to determine machine architecture.
Set the environment variable FLUENT_ARCH and try again
Comments: Check the OS version using the commands, uname -r and uname -v respectively. If the output is AIX 1 6 then you are running AIX 6.1 and is not supported with ANSYS FLUENT 12. The problem comes from the /ansys_inc/v120/fluent/bin/fluent_arch1.0 file not having a reference to this version of AIX.
Workaround: You can set the FLUENT_ARCH environment variable manually with a value of: aix51_64 or you can download a revised fluent_arch1.0 file that has been modified for this OS version. Rename the current one in the /ansys_inc/v120/fluent/bin/ directory to fluent_arch1.0_original and replace it with the one you downloaded. (See Resolution Document)
NOTE: This will also not be officially supported until ANSYS FLUENT Version 13 due out end of next year.