s2ch: 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/s2ch - from package: scheme2c

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

Error in other languages:
s2ch: bevel nie gevind nie
s2ch: comandă negăsită
s2ch: comando não encontrado
s2ch: commande introuvable
s2ch: command not found
s2ch: käsku ei ole
s2ch: không tìm thấy lệnh
s2ch: komanda nerasta
s2ch: Kommando nicht gefunden.
s2ch: kommandot finns inte
s2ch: komut yok
s2ch: nie znaleziono polecenia
s2ch: níor aimsíodh an t-ordú
s2ch: no se encontró la orden
s2ch: no s'ha trobat l'ordre
s2ch: opdracht niet gevonden
s2ch: parancs nem található
s2ch: perintah tidak ditemukan
s2ch: príkaz nenájdený
s2ch: příkaz nenalezen
s2ch: команда не найдена
s2ch: командата не е открита
s2ch: 命令找不到
s2ch: コマンドが見つかりません