h5convert: 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/lib/yorick/bin/h5convert - from package: yorick-hdf5

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

Error in other languages:
h5convert: bevel nie gevind nie
h5convert: comandă negăsită
h5convert: comando não encontrado
h5convert: commande introuvable
h5convert: command not found
h5convert: käsku ei ole
h5convert: không tìm thấy lệnh
h5convert: komanda nerasta
h5convert: Kommando nicht gefunden.
h5convert: kommandot finns inte
h5convert: komut yok
h5convert: nie znaleziono polecenia
h5convert: níor aimsíodh an t-ordú
h5convert: no se encontró la orden
h5convert: no s'ha trobat l'ordre
h5convert: opdracht niet gevonden
h5convert: parancs nem található
h5convert: perintah tidak ditemukan
h5convert: príkaz nenájdený
h5convert: příkaz nenalezen
h5convert: команда не найдена
h5convert: командата не е открита
h5convert: 命令找不到
h5convert: コマンドが見つかりません