dfits: 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/dfits - from package: qfits-tools

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

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