ltsp-genmenu: 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/ltsp-genmenu - from package: ltsp-client-core

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

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