From my experience, there are always a step or so that does not resolve the way it should; hence this document.
WordPress Version 3.5+ allows multi-sites, so you can install WordPress in it’s own directory, powering the site from it’s root (http://example.com).
This method is cleaner, more secure way of archiving your WordPress.
Here are the steps I took, in Migrating WordPress.
NOTE: make any required backups before you perform any type of edits to your site. You will require a text editor, such as Notepad++ (preferred) to perform the following tasks.
First Step
downloaded WordPress 3.5+ and installed it in a desired directory /wordpress/ (e.g. http://example.com/wordpress/)
Second Step
Copy your index.php & .htaccess files to your root and perform the following edits to them.
Edit the index.php (line #17) file by including the directory where your WordPress resides.
Line# 17: require ( dirname( __FILE__ ) . ‘wordpress/wp-blog-header.php’ )
NOTE: do not include the / in front of wordpress (‘/wordpress/wp-..), otherwise it won’t work.
Third Step
Edit the .htaccess file you copied over to the root.
Remove the directory name /wordpress from the .htaccess: RewriteRule ./wordpress /index.php [L]
RewriteRule . /index.php [L]
Final Setp
Go to Dashboard > Settings > General and adjust the following: Site Address (URL) http://example.com/wordpress/ over to: http://example.com
Visitors can access your WordPress from the root directory (e.g. http://example.com). Log into dashboard will still direct to where wordpress core files are located: http://example.com/wordpress/wp-admin/
NOTE: I strongly suggest using All In One WordPress Security and Firewall Plugin and secure your login access and follow through recommended features.
Resources
WordPress Codex: http://codex.wordpress.org/Moving_WordPress
Ask WordPress Girl: http://askwpgirl.com/how-do-i-move-wordpress-from-a-subdirectory-to-the-root-directory/