browse server issue

I wanted to create a link in FCKEditor. When I clicked Browse Server, I got following message in a new opened window:

Not Found

The requested URL /fckeditor/editor/filemanager/browser/default/browser.html was not found on this server.

But when I entered http://mysite/fckeditor/editor/filemana ... owser.html in the browser, I got a popup window said:

The server didn't reply with a proper XML data. Please check your configuration.

Any help?
Thanks in advance.