ipwatchd-script: 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 CentOS possible default full paths are:

/usr/sbin/ipwatchd-script - from package: ipwatchd

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/ipwatchd-script - from package: ipwatchd

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

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