This error is caused by the wrong path to the fckeditor. i.e. the value of the $oFCKeditor->BasePath
is wrong in your code. Because of this, the server generates a 404 error, because the file can not be found on the server.
By default, in the tutorial, it uses an absolute path relative to the host name. In otherwords, it expects the fckeditor to be in www.example.com/fckeditor/
. However, if this is not the case for you, and, for example your fckeditor is located in www.example.com/mysite/fckeditor/
, then the value of the $oFCKeditor->BasePath
should be changed to /mysite/fckeditor/
instead. Also, make sure the capitalization is correct, if the server is UNIX based.