You would want to clear your DNS (domain name system) cache if you are getting unexpected results when performing processes which require transfereing data over the Internet or LAN (local area network).
 
DNS is what resovles a domain name, such as www.mycompany.com to a physical computer IP address (internet protocol address). DNS records have a TTL (time to live) refresh rate which your local PC caches to reduce network traffic so it will not always have the latest information that is available. If you want to refresh this cache manually enter the following command from a DOS prompt.  (Close all browsers before performing this step)

On most Windows machines you can get to a DOS prompt by going to START > Search “CMD” > Open CMD option that appears under 'Programs.' 

At the command line type C: to inusure you are applying commands to the local PC. Then, after the C:\> first type “CD\” and hit ENTER - this will get you to the root. Then type “ipconfig /flushdns"

The resulting output should be “Successfully flushed the DNS Resolver Cache.”

This will clear out your local cache and force it to look to DNS for new information.