sd-c: 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/sd-c - from package: snowdrop

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

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