Ruby on rails 我已经安装了Ruby 2.0.0和rails 3.1.12。我正在尝试启动服务器，但出现以下错误：

我尝试了很多答案，比如，在wiki上遵循devkit步骤，但是我陷入了“ruby dk.rb安装”步骤。我在

config.yml

文件中包含了ruby安装路径，然后错误仍然存在

我还修改了环境变量以包含路径。然后我也失败了

请帮我解决这个问题

我的

config.yml

文件如下所示：

ERROR:  Error installing json:
        The 'json' native gem requires installed build tools.

Please update your PATH to include build tools or download the DevKit
from 'http://rubyinstaller.org/downloads' and follow the instructions
at 'http://github.com/oneclick/rubyinstaller/wiki/Development-Kit'

---

您使用的是windows系统还是linux？@Bharat我当前使用的是windows7@Bharasoni我已经尝试了所有这些步骤。这对我没用。我仍然无法安装json Gem。这是我在运行Devkit命令时遇到的错误。C:\Devkit>ruby dk.rb初始化完成！请检查并修改自动生成的“config.yml”文件，以确保它包含您希望通过DevKit增强的所有已安装Rubies的根目录。C:\Devkit>ruby dk.rb安装无效配置或未列出ruby。请修复'config.yml'并重新运行'ruby dk.rb install'

# This configuration file contains the absolute path locations of all
# installed Rubies to be enhanced to work with the DevKit. This config
# file is generated by the 'ruby dk.rb init' step and may be modified
# before running the 'ruby dk.rb install' step. To include any installed
# Rubies that were not automagically discovered, simply add a line below
# the triple hyphens with the absolute path to the Ruby root directory.
#
# Example:
#
# ---
# - C:/ruby19trunk
# - C:/ruby192dev
#
---