tcpbsi: 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/tcpbsi - from package: ion

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

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