adf2hdf: 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/adf2hdf - from package: cgns-convert

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

Error in other languages:
adf2hdf: bevel nie gevind nie
adf2hdf: comandă negăsită
adf2hdf: comando não encontrado
adf2hdf: commande introuvable
adf2hdf: command not found
adf2hdf: käsku ei ole
adf2hdf: không tìm thấy lệnh
adf2hdf: komanda nerasta
adf2hdf: Kommando nicht gefunden.
adf2hdf: kommandot finns inte
adf2hdf: komut yok
adf2hdf: nie znaleziono polecenia
adf2hdf: níor aimsíodh an t-ordú
adf2hdf: no se encontró la orden
adf2hdf: no s'ha trobat l'ordre
adf2hdf: opdracht niet gevonden
adf2hdf: parancs nem található
adf2hdf: perintah tidak ditemukan
adf2hdf: príkaz nenájdený
adf2hdf: příkaz nenalezen
adf2hdf: команда не найдена
adf2hdf: командата не е открита
adf2hdf: 命令找不到
adf2hdf: コマンドが見つかりません