The version of CKEditor could not be detected
What you need to do after installing the module is go to http://ckeditor.com and download the latest version. Then uncompress the contents of the 'ckeditor' directory of the downloaded file to this folder 'libraries/ckeditor/ckeditor'.

Installation steps


Unzip the module files to the "sites/all/libraries" directory. It should now
  contain a "ckeditor" directory.
Download standalone CKEditor from http://ckeditor.com/download. Unzip the
  contents of the "ckeditor" directory from the installation package to the
  "sites/all/libraries/ckeditor/ckeditor" directory.
  Note: you can skip uploading the "_samples" and "_source" folders.
Enable the module in the "Administration panel > Modules > User Interface" section.
Grant permissions for using CKEditor in the
  "Administration panel > People > Permissions" section.
  Note: In order to enable the file browser, refer to the
        "Installing CKFinder" section.
Adjust CKEditor profiles in the
  "Administration panel > Configuration > Content Authoring > CKEditor" section.
  Profiles determine which options are available to users based on the input format system.