can't able to edit the value in the rails

I create the project in scaffold but I cant able to edit it and update
th values

I gort the error in no action required I attach the image bellow
and my codeing the controller is :

@department = Department.find(params[:id])

    respond_to do |format|
      if @department.update_attributes(params[:departments])
        flash[:notice] = 'Department was successfully updated.'
        format.html { redirect_to(@department) }
        format.xml { head :ok }
      else
        format.html { render :action => "edit" }
        format.xml { render :xml => @department.errors, :status =>
:unprocessable_entity }
      end
    end

Attachments:
http://www.ruby-forum.com/attachment/8184/edit.jpg

I create the project in scaffold but I cant able to edit it and update
th values

I guess you are a beginner in Rails. If so then I suggest that you
work right through a good tutorial such as railstutorial.org, which is
free to use online. That will show you the basics of Rails.

Once you have done that, if you still get the problem, and still
cannot work it out then have a look at the Rails Guide on Debugging,
which will show you techniques that can be used to debug your code.

If you have to post messages in future then please paste them in as
text rather than an image. It is easier to follow the thread if
everything is in the message.

Colin