Sometimes you may have problems getting into a site from a public computer. You can try clearing the cache to delete any cookies that may exist. The basic method of clearing the cache is to go to the menu at the top of the screen, click on Tools, choose Options, and choose something that says "Empty Cache."

In Internet Explorer, choose: Tools ==> Internet Options ==> Browsing History

click Delete

In Firefox, choose Tools ==> Clear Private Data

and select the Cookies to delete.