I'm a fellow WordPress enthusiast and a Happiness Engineer at Automattic, the folks behind WordPress.com.
In order for your domain to work properly, you'll also have to go into your WordPress dashboard and under…"
"The next thing that I would try is to rename the .htaccess file. It's a little tricker to do, since this is a hidden file. It's normally in the root folder and you'll have to view hidden files in your FTP editor.
Give that a try."
"In your FTP client, navigate to wp-content/plugins and rename the plugins folder to anything else. I like to add an underscore to the name, so it's now plugins_
This will disable all of your plugins and you'll be able to log in. Then you…"