404 error when inserting a table in ckeditor

I am using CkEditor in my application.When I click "Table" button from toolbar a dialog window pops up.When I specify row and columns to be inserted and click on OK I am getting the following error in an another pop up window which is part of browser.

Error 404----Not found. From RFC 2068 Hypertext transfer Protocol--Http/1.1 10.4.5 Not found.The server hasn't found anything matching the request URI.No Indication is given of whether the condition is temporary or Permanent. If the server doesn't wish to make this information available to client,the status code 403(Forbidden) can be used instead.The 410(Gone) status code should be if the server knows ,through the some internally configurable mechanism , that an old resource is permanently unavailable and has no forwarding address.