Your network contains an Active Directory forest named contoso.com.
Users frequently access the website of an external partner company. The URL of the
website is http://partners.adatum.com.
The partner company informs you that it will perform maintenance on its Web server and that
the IP addresses of the Web server will change.
After the change is complete, the users on your internal network report that they fail to
access the website. However, some users who work from home report that they can access
the website.
You need to ensure that your DNS servers can resolve partners.adatum.com to the correct
IP address immediately.
What should you do?

A.
Run dnscmd and specify the CacheLockingPercent parameter.

B.
Run Set-DnsServerGlobalQueryBlockList.

C.
Run ipconfig and specify the Renew parameter.

D.
Run Set-DnsServerCache.

Explanation:
http://technet.microsoft.com/en-us/library/jj649852.aspx
Run Set-DnsServerCache with the -LockingPercent switch. dnscmd technically works also.