ffindex_apply: 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/ffindex_apply - from package: ffindex

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

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