Error installing "nokogiri" in a Ruby on Rails application?

I've been following along with the Lynda.com's Ruby on Rails course. I did everything just as mentioned inside the videos.

I am trying to run the rails server command, which should default to WEBrick, correct?

I run the command and it has an issue in the nokogiri.rb file and on line 29 where the error is happening this is what is read:

require 'nokogiri/nokogiri'

Which is what my command prompt is throwing up on when running the rails server command. Any idea what could be causing this? If so, what commands do I need to run to settle this? To me it sounds like something was missed when installing MySQL.

I am not sure what nokogiri is and why rails server won't run and points to that line of code.

The path to this file is (Wherever you installed the folder to)\lib\ruby\gems\2.2.0\gems\nokogiri-1.6.6.2-x64-mingw32\lib

EDIT**: I have a chain of errors, like it goes from -long path-, from -longpath- etcetera. I tried installing the latest gem, and it wasn't successful. Is there a log file I can get to share with you guys to help figure out the issue.