bpsendfile: 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 Debian possible default full paths are:

/usr/bin/bpsendfile - from package: ion

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