file_name.erb: 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/lib/ruby/gems/1.8/gems/hoe-3.13.0/template/bin/file_name.erb - from package: rubygem-hoe

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

On Debian possible default full paths are:

/usr/share/ruby-hoe/template/bin/file_name.erb - from package: ruby-hoe

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

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