euare-usercreatecert: 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/euare-usercreatecert - from package: euca2ools

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

On Debian possible default full paths are:

/usr/bin/euare-usercreatecert - from package: euca2ools

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

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