ISP DNS servers are usually can be used by their customers only.
If you need a public DNS server, Google http://code.google.com/speed/public-dns/docs/using.html and some other companies provides them http://www.tech-faq.com/public-dns-servers.html


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>After following your recommendation and still not getting results I searched some more and found out that changing the DNS settings solved the problem.
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>My best guess is that the previous DNSes, which work fine at home where I set up the machine, do not work at the office. At the office I use a different ISP and the previous DNSes may be associated with the home ISP and do not wish to give information to other users.
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