請問奇摩的問題

我所有網站都可以上唯獨奇摩上不去出現這種訊息要怎麼解決
ERROR
The requested URL could not be retrieved

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While trying to retrieve the URL: http://tw.yahoo.com/

The following error was encountered:

Unable to forward this request at this time.
This request could not be forwarded to the origin server or to any parent caches. The most likely cause for this error is that:

The cache administrator does not allow this cache to make direct connections to origin servers, and
All configured parent caches are currently unreachable.
Your cache administrator is root@proxy.nctu.edu.tw.



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Generated Mon, 27 Oct 2003 03:24:31 GMT by wproxy2.nctu.edu.tw (squid/2.5.STABLE2)