the requested URL could not be retrieved?

hello,
sometimes when I want to connect to a web site squid gives this error
but when I connect to internet directly then I am able to get into this
page...
what may be wrong?
why does not squid check the object if it is there or not?
I guess it is giving this from its cache...but why?

ERROR
The requested URL could not be retrieved
While trying to retrieve the URL:
http://www.hurriyet.com.tr/hur/turk/98/08/06/spor/07spo.htm
The following error was encountered:
     Connection Failed
The system returned:
    (65) No route to host
This means that:
    The remote site or server may be busy or down. Please try again
later.
Generated by squid/1.NOVM.22@turkey.ispro.net.tr
Received on Thu Aug 06 1998 - 13:00:52 MDT