sanduhr: 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/sanduhr - from package: sanduhr

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

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