fdf2fit: command not found

Have You tried accessing the binary with the full path?

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 CentOS possible default full paths are:

/usr/bin/fdf2fit - from package: grace

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/fdf2fit - from package: grace

You may install the required package with command apt-get install {package}
Error in other languages:
fdf2fit: bevel nie gevind nie
fdf2fit: comandă negăsită
fdf2fit: comando não encontrado
fdf2fit: commande introuvable
fdf2fit: command not found
fdf2fit: käsku ei ole
fdf2fit: không tìm thấy lệnh
fdf2fit: komanda nerasta
fdf2fit: Kommando nicht gefunden.
fdf2fit: kommandot finns inte
fdf2fit: komut yok
fdf2fit: nie znaleziono polecenia
fdf2fit: níor aimsíodh an t-ordú
fdf2fit: no se encontró la orden
fdf2fit: no s'ha trobat l'ordre
fdf2fit: opdracht niet gevonden
fdf2fit: parancs nem található
fdf2fit: perintah tidak ditemukan
fdf2fit: príkaz nenájdený
fdf2fit: příkaz nenalezen
fdf2fit: команда не найдена
fdf2fit: командата не е открита
fdf2fit: 命令找不到
fdf2fit: コマンドが見つかりません