I kept receiving this message after clicking the back button. It only occurs at certain hours of a day.
"Warning: Page has Expired The page you requested was created using information you submitted in a form. This page is no longer available. As a security precaution, Internet Explorer does not automatically resubmit your information for you.
To resubmit your information and view this Web page, click the Refresh button."
It does occur when you go back to a page that was requested using a POST request instead of the normal GET request. Which happens, for example, for searches. It's not something we have under control at all.
The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - Heraclitus