On a computer that is running an x64-based version of Windows Server 2003 or of Windows XP, 32-bit applications may not use the Domain Name System (DNS) cache. Even though the name that an application tries to resolve is present in the DNS cache, a DNS query is sent to a DNS server.
This behavior may generate unwanted network traffic. Also, name resolutions that use a DNS server may be slower than resolutions that use the cached entry.
Note This problem does not occur in Windows Server 2008.
To work around this behavior, add the names that you want to resolve to the hosts file. The application consults the hosts file before it contacts a DNS server.
By using this workaround, you can avoid unnecessary queries, and reduce the resolution time.