This is a lng shot, but it could be settings in your browser. Are you accessing both of these addresses using the same browser on the same machine? Have you tried using a different browser on the smae machine or a different machine altogether?

The issue could be caused by security settings associated with security zones, especially if you're using Internet Explorer. The http://Hostname URL could be recognized as an intranet zone site running under trusted security where loading controls like FreeTextBox is fairly unrestricted, and http://www.domainname.com could be recognized as an Internet zone site with greater restrictions.

If you're using Internet Explorer, look in the lower right hand corner on the status bar. It'll tell you what zone you are in.

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