rt-attributes-viewer: 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/sbin/rt-attributes-viewer - from package: rt3

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

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