I have verified it's saving my new username in the publishing settings and yes, I'm seeing the error based on the posting status. I get the following ...FTP login failed (server: ftp.domain.com, username: myoldusername, reason: 530 User myoldusername cannot log in. )
Are you seeing this behaviour, when trying to publish your blog?
- What is the blog URL?
- What is the FTP server setting?
- When did you make the setting change?
- Did you verify the problem, by examining the host server activity logs?