(defun news-check ()
 (condition-case err
     (message "The result is %s" (gnus-group-get-new-news))
   (news-error
    (message "I expect the server closed again %s",err)
    )
   )
)

I could be mistaken in this, but in your code above, where did you get 'news-error' as the name of the error condition raised? I can't find this anywhere in the gnus source tree. Do you know for sure that gnus-group-get-new-news (or anything it calls) raises that condition?