Can't access WordPress dashboard

I am attempting to move my new wordpress files to my replace the files on my existing website. I began following the directions at http://codex.wordpress.org/Moving_WordPress, I referenced the section entitled “Changing Your Domain Name and URLs
Moving a website and changing your domain name or URLs (i.e. from http://example.com/site to http://example.com, or http://example.com to http://example.net) requires the following steps – in sequence.” Perhaps I should have referred to the next section “Moving Directories On Your Existing Server,” since my sandbox site is simply an addon domain on the same server.

To clarify, I have an addon domain (http://example.net) that I’m using as a sandbox to create a new version of my website. I wanted to move those files to the primary (http://example.com) domain, to replace the files that exist there currently.

Anyhow, under the “Moving a website…” section I began following the steps listed there. Step 4 states: “Log in to the site you want to move and go to Settings > General, then change the URLs. (ie from http://example.com/ to http://example.net ) – save the settings and expect to see a 404 page.” Unfortunately, after doing this, I didn’t see a 404 page. Instead, I was prompted to login to my admin dashboard again. However, when I try to login to the .net site, I get redirected to the .com login screen. In other words, the http://example.net site now thinks that it is http://example.com. There appears to be no way to login to the admin page for the http://example.net site.

How do I fix this? Is there a file that I can access to change both the WordPress Address (URL) and the Site Address (URL) back to the .net suffix?

Thanks,
Tim