sofa: 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 Debian possible default full paths are:

/usr/bin/sofa - from package: sofa-apps

You may install the required package with command apt-get install {package}

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