can some one please tell me how to override the DNS look up in windows XP... there are a few sites i visit regularly.. but now for past few days i cant open up a few of them.. everytime i type in the url and hit enter... i straight away get this erroe message..

Bad Gateway
The following error occurred:
[code=DNS_HOST_NOT_FOUND] The host name was not found during the DNS lookup. Contact your system administrator if the problem is not found by retrying the URL.


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Please contact the administrator.



Now i think tht my ISP has got certain problems with the DNS server ..and isnt able to resolve the hostname...

if u guys think tht its something else..pls let me know.. and if it is the same thing.. then please tel me how to over ride the DNS look up... i have tried putting the ip address of the sites in my hosts file but no use...

pls help..