kxsrun: 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/kxsrun - from package: kscreensaver-xsavers

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

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