First, I'm sorry about my English.
I have a problem. When my blog doesn't have any user, I can post with my admin account with another nickname (so the sentence POST BY on the homepage would appear with my nickname). After that, there were 3 friends of mine registerd for 2 author and 1 editor. From that time, when I write new post, the Post Author section does not list my admin name or nick name anymore, just 3 new author/editor. I cannot post with my admin account anymore and I have to create another admin account with different name to post.
You guys have any idea? I searched google but there's no topic about this. I'm using 2.6.1 anyway.