paw++-g77: command not found

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/bin/paw++-g77 - from package: paw-g77

You may install the required package with command yum install {package}

Error in other languages:
paw++-g77: bevel nie gevind nie
paw++-g77: comandă negăsită
paw++-g77: comando não encontrado
paw++-g77: commande introuvable
paw++-g77: command not found
paw++-g77: käsku ei ole
paw++-g77: không tìm thấy lệnh
paw++-g77: komanda nerasta
paw++-g77: Kommando nicht gefunden.
paw++-g77: kommandot finns inte
paw++-g77: komut yok
paw++-g77: nie znaleziono polecenia
paw++-g77: níor aimsíodh an t-ordú
paw++-g77: no se encontró la orden
paw++-g77: no s'ha trobat l'ordre
paw++-g77: opdracht niet gevonden
paw++-g77: parancs nem található
paw++-g77: perintah tidak ditemukan
paw++-g77: príkaz nenájdený
paw++-g77: příkaz nenalezen
paw++-g77: команда не найдена
paw++-g77: командата не е открита
paw++-g77: 命令找不到
paw++-g77: コマンドが見つかりません