The Domain Name Service (DNS) translates URL's into IP addresses. For example, when you type www.website.com into a browser DNS translates that into the IP address xxx.xxx.xxx.xxx. To speed up DNS, queries are cached so successive attempts are resolved via the cache instead of constantly querying a DNS server.

The problem is by default Windows 2000 and XP cache unsuccessful DNS queries for 5 minutes. This can prevent your from accessing this resource until cache expires or is cleared manually. This Reduce the time an unsuccessful DNS query cache from 5 minutes to 1 minute. This will only modify unsuccessful DNS queries.

To change this, follow the next steps:

1. Open the Registry Editor click on the Start button on your taskbar, then click on Run and type "regedit" and click on OK to start the regedit utility.
    
2. Expand HKEY_LOCAL_MACHINE\System\CurrentControlSet\ Services\DnsCache\Parameters (see picture 1).
   
   

   Picture 1

3. Create a new DWORD value or modify the existing value called "NegativeCacheTime" and set the value to "60".
    
4. The modifications you made will be in effect after you logout or reboot your PC.