smfsh: 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/smfsh - from package: smf-utils

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

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