xwatch: 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/xwatch - from package: xwatch

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

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