Authors & Users – BLANK

I have a blog which have been using wordpress since early 2007. At that point, admin was not the default username given at first activation of the blog.

My problem is actually with Authors & Users. It does not list any users anymore since 2.7.1. The administrator’s login id for the blog is not admin.

I have initiated a force take back on ‘admin’ by changing its email to an email which i have access to. And initiate a password recovery.

Upon successfully resetting the password and obtaining the temporary password I still could not login. Any attempt was greeted with the following response: ERROR: Invalid username.

So, this is a 2 fold question.
1. Why is the Authors & Users blank for the Administrator (not admin username)
2. Why I could not login username admin (normal subscriber)? And how can i recover from this?