If you have a wordpress blog, you must have noticed in your admin settings page that you cannot change your login name once it is set. So, you believe that once you get some stereotypical name like Admin(default) you cannot change it later like you MSN or Gmail username. In case of single author blogs, people generally leave the username to default i.e. admin, which everyone can pretty much guess on. Besides, you might also want to change the login while moving your wordpress blog to a new domain. Even if you have a multi-author blog, you might need to change the username for other contributing writers for some reasons. You cannot do it via the Admin interface but can do it very easily from PhpMyAdmin.
You first need to login to your phpmyadmin from your Hosting’s Admin. If you have a number of databases, go ahead and select the one that contains your Worpdress blog.
Now, you’ll see the tables used in your WordPress database. Go ahead and click on “wp_users” on the left hand panel. You will see a small pencil icon next to before every username in the list.
Click on the one you need to edit. Now you’ll see a number of fields like user_login, user_nicename etc. To change the login name, you should change the value seen for “user_login”. Change it to whatever you like and you’re done.
Finally click on the Go button at the bottom. Now the new login name will be applicable while signing in to the blog for the particular username.