exrblur: 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/exrblur - from package: exrtools

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

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