bsfilter: 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/bsfilter - from package: bsfilter

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

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