TranMain_openmpi: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/openmpi/bin/TranMain_openmpi - from package: openmx-openmpi

You may install the required package with command yum install {package}
Error in other languages:
TranMain_openmpi: bevel nie gevind nie
TranMain_openmpi: comandă negăsită
TranMain_openmpi: comando não encontrado
TranMain_openmpi: commande introuvable
TranMain_openmpi: command not found
TranMain_openmpi: käsku ei ole
TranMain_openmpi: không tìm thấy lệnh
TranMain_openmpi: komanda nerasta
TranMain_openmpi: Kommando nicht gefunden.
TranMain_openmpi: kommandot finns inte
TranMain_openmpi: komut yok
TranMain_openmpi: nie znaleziono polecenia
TranMain_openmpi: níor aimsíodh an t-ordú
TranMain_openmpi: no se encontró la orden
TranMain_openmpi: no s'ha trobat l'ordre
TranMain_openmpi: opdracht niet gevonden
TranMain_openmpi: parancs nem található
TranMain_openmpi: perintah tidak ditemukan
TranMain_openmpi: príkaz nenájdený
TranMain_openmpi: příkaz nenalezen
TranMain_openmpi: команда не найдена
TranMain_openmpi: командата не е открита
TranMain_openmpi: 命令找不到
TranMain_openmpi: コマンドが見つかりません