bs2bconvert: 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 CentOS possible default full paths are:

/usr/bin/bs2bconvert - from package: libbs2b

You may install the required package with command yum install {package}

Error in other languages:
bs2bconvert: bevel nie gevind nie
bs2bconvert: comandă negăsită
bs2bconvert: comando não encontrado
bs2bconvert: commande introuvable
bs2bconvert: command not found
bs2bconvert: käsku ei ole
bs2bconvert: không tìm thấy lệnh
bs2bconvert: komanda nerasta
bs2bconvert: Kommando nicht gefunden.
bs2bconvert: kommandot finns inte
bs2bconvert: komut yok
bs2bconvert: nie znaleziono polecenia
bs2bconvert: níor aimsíodh an t-ordú
bs2bconvert: no se encontró la orden
bs2bconvert: no s'ha trobat l'ordre
bs2bconvert: opdracht niet gevonden
bs2bconvert: parancs nem található
bs2bconvert: perintah tidak ditemukan
bs2bconvert: príkaz nenájdený
bs2bconvert: příkaz nenalezen
bs2bconvert: команда не найдена
bs2bconvert: командата не е открита
bs2bconvert: 命令找不到
bs2bconvert: コマンドが見つかりません