rainbow-resume: 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/sbin/rainbow-resume - from package: rainbow

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

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