sfxtest: 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/sfxtest - from package: awesfx

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

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