A Complete Guide to Install Ruby and Rails on Windows

As usual, whenever I find a problem with something and then another problem appears with no guide except Google and my experience (if any), I make my own guide. This time it is a guide to installing Ruby then Rails on Windows.

Step 1 - Install Ruby (Ruby 1.9.3-p327 while writing this post) through RubyInstaller:

It is as easy as any other Windows Installer. Just go to RubyInstaller download page and download it. One thing to notice while installing is to check the option to add Ruby executables to your PATH, and maybe file association if you wish. Note: Make sure the installation path does not have spaces (like: Program Files) to avoid any terminal errors later.

Step 2 - Install Development Kit (DevKit-tdm-32-4.5.2-20111229-1559-sfx.exe  while writing this post):

As their page says: "The RubyInstaller Development Kit (DevKit) is a MSYS/MinGW based toolkit than enables you to build many of the native C/C++ extensions available for Ruby." It will be needed to install some 'gems' for Rails later. The executable is no more than a 7zip archive that can be extracted to a folder of choice.

After extracting the folder,
- Open the command line (cmd) as administrator (Shift+Enter or right click and 'run as administrator') and browse to the devkit  directory.
- If we step to the normal step mentioned in the RubyInstaller Development Kit Wiki we will get an error like this: " registry.rb:172:in `find': unknown > > encoding name > > - CP720 (ArgumentError) ". So first, let's write this in the command line:
chcp 1256
- Next, let's initialize the devkit:
ruby dk.rb init
-  Make sure the generated "config.yml" file includes the right Ruby version.
- Next install devkit:
ruby dk.rb install
- You can follow the RubyInstaller Development Kit Wiki instructions to make sure it is installed properly.

Step 3 - Install Some Gems for Rails:

When installing Rails later, it will require some gems to install. So let's install them now.
- From command line, write:
gem install json -v  '1.7.5'
gem install coffee-rails -v '3.2.2'
- Wait for the download and installation to end.

Step 4 - Install Rails

- From command line, write:
gem install rails
- Wait for the download and installation to end.

Step 5 - First Rails Project

- From command line, cd to the folder of your choice or write the full path in the following line:
rails new ./projects/test_proj
- Wait for file creation to end, then cd to the project file.
- Write:
rails s
and your first Ruby on Rails service will be online on "localhost:3000"

Now you have your environment ready for Ruby on Rails development.