keytest: 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/keytest - from package: esekeyd

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

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