sass2css: 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/sass2css - from package: libtext-sass-perl

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

Error in other languages:
sass2css: bevel nie gevind nie
sass2css: comandă negăsită
sass2css: comando não encontrado
sass2css: commande introuvable
sass2css: command not found
sass2css: käsku ei ole
sass2css: không tìm thấy lệnh
sass2css: komanda nerasta
sass2css: Kommando nicht gefunden.
sass2css: kommandot finns inte
sass2css: komut yok
sass2css: nie znaleziono polecenia
sass2css: níor aimsíodh an t-ordú
sass2css: no se encontró la orden
sass2css: no s'ha trobat l'ordre
sass2css: opdracht niet gevonden
sass2css: parancs nem található
sass2css: perintah tidak ditemukan
sass2css: príkaz nenájdený
sass2css: příkaz nenalezen
sass2css: команда не найдена
sass2css: командата не е открита
sass2css: 命令找不到
sass2css: コマンドが見つかりません