If you are viewing a web page that you believe has been updated but you can not see the updated page, firstly try F5 or CTRL+F5 to force a refresh of that page. If that fails try clearing your DNS Cache:
Windows® XP, 2000, or Vista®
1. Open the Start menu.
2. Go to Run. If you do not see the Run command in Vista, search for “run” in the Search bar.
3. In the Run text box, type: ipconfig /flushdns
4. Press Enter or Return, and your cache will be flushed.
1. Go to Applications.
2. Go to Utilities.
3. Open the Terminal application.
4. Type: dscacheutil -flushcache
5. Press Enter or Return, and your cache will be flushed.