balsa-ab: 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/balsa-ab - from package: balsa

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

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