tzwatch: 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/tzwatch - from package: tzwatch

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

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