screenkey: 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/screenkey - from package: screenkey

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

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