Installing Demo Content

I’ve followed these instructions to install demo content onto my website:

To import this information into a WordPress site follow these steps: –>
<!– 1. Log in to that site as an administrator. –>
<!– 2. Go to Tools: Import in the WordPress admin panel. –>
<!– 3. Install the “WordPress” importer from the list. –>
<!– 4. Activate & Run Importer. –>
<!– 5. Upload this file using the form provided on that page. –>
<!– 6. You will first be asked to map the authors in this export file to users –>
<!– on the site. For each author, you may choose to map to an –>
<!– existing user on the site or to create a new user. –>
<!– 7. WordPress will then import each of the posts, pages, comments, categories, etc. –>
<!– contained in this file into your site. –>

However, when installed no demo content actually shows up in my dashboard. Whenever I try to install I get an error message saying that content already exists.

Can you please help me troubleshoot this or suggest a definitive way of installing demo content?