kscreen-console: 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/kscreen-console - from package: kscreen

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

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