abx: 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/abx - from package: abx

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