abr2gbr: 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/abr2gbr - from package: abr2gbr

You may install the required package with command apt-get install {package}
Error in other languages:
abr2gbr: bevel nie gevind nie
abr2gbr: comandă negăsită
abr2gbr: comando não encontrado
abr2gbr: commande introuvable
abr2gbr: command not found
abr2gbr: käsku ei ole
abr2gbr: không tìm thấy lệnh
abr2gbr: komanda nerasta
abr2gbr: Kommando nicht gefunden.
abr2gbr: kommandot finns inte
abr2gbr: komut yok
abr2gbr: nie znaleziono polecenia
abr2gbr: níor aimsíodh an t-ordú
abr2gbr: no se encontró la orden
abr2gbr: no s'ha trobat l'ordre
abr2gbr: opdracht niet gevonden
abr2gbr: parancs nem található
abr2gbr: perintah tidak ditemukan
abr2gbr: príkaz nenájdený
abr2gbr: příkaz nenalezen
abr2gbr: команда не найдена
abr2gbr: командата не е открита
abr2gbr: 命令找不到
abr2gbr: コマンドが見つかりません