This is a problem that occurs when a browser is using "cached" pages. This is very simple to remedy. Follow the instructions below for your browser and you'll be all set.

1. For users of Internet Explorer (the preferred browser) click "View" then "Internet Options" and in the section for Temporary Internet Files, click the settings button. Select the button for "Check for newer versions of stored pages... Every visit to to the page."

2. For users of Netscape, under Edit select Preferences, then Advanced. Under the Cache section, Document in cache compared to document on network should be set to "Every time".