Windows XP caches DNS entries (these change human-readable names such as malektips.com and google.com into IP addresses that allow communication over the Internet). This way instead of having to access a remote DNS server every time you re-access the same web address, Windows can use the cached entry to speed communication.

If a negative response is retrieved when performing a DNS query, this negative response may also be cached. If temporary problems exist with your Internet connection or DNS server, it is possible that the query for a domain that should match with an IP address fails. As this failure is recorded, if network problems cease, future requests for the particular site will continue to fail for awhile as Windows uses the failed cached entry instead of checking with a DNS server. However, it is relatively simple to clear the DNS Resolver Cache if you are temporarily unable to access your favorite site:

1. Click the "Start" button, selecting "Run".

2. Type ipconfig /flushdns and press Enter.

If this fails to work you may wish to run this command at the DOS prompt, allowing you to see its output:

1. Click the "Start" button, selecting "Run".

2. Type cmd and press Enter.

3. The command prompt appears. Type ipconfig /flushdns and press Enter.

4. When done, close the command prompt by clicking the "X" at the top-right of the window.

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