euare-userlistcerts: 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-userlistcerts - from package: euca2ools

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

On Debian possible default full paths are:

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

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

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