When you visit a web page, your browser may store a copy of it in its local cache. As a result, when you revisit the page, the browser may display the old copy it had previously stored rather than reload the latest version from the web. Since the Help actually consists of a set of web pages, you might need to clear your web browser’s cache to force it to load the latest version. For example, in Internet Explorer, go to Tools > Safety > Delete Browsing History (or press Ctrl + Shift + Del), select Temporary Internet files, then click Delete.
Clearing the Cache in Internet Explorer