conchftp: 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/conchftp - from package: python-twisted-conch

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

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