Why do duplicate messages sometimes appear on the Guestbook?
When you fill in the form and hit “Enter” the Guestbook script adds your message and takes you back to the normal view of the board all in one go. If you refresh this page your browser still has this “message posting” information in its cache and will repeat the post (you may get a prompt to the effect that the page cannot be refreshed without resending data). You may even not have deliberately refreshed the page, but if you browse ahead to other pages, and then use your Back button to return to it, the effect is the same. You can avoid the problem by always going back in your browser to a point before you made your post, and reloading the GB page from there.
