dtpcclock: 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/dtpcclock - from package: ion

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

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