flextra.ecmwf: 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/flextra.ecmwf - from package: flextra

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

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