I have an HTML login page (form). Upon successful login, my perl script generates a session ID, which I embed in all the URL links. When the user logs out, I remove the session id from the session database. However, if I click the "Back" button, I get this error message: "The page cannot be refreshed without resending the information. Click Retry to send the information again, or click Cancel to return to the page that you were trying to view." When I click "Retry," the login information in the HTML form is re-sent to the web server. This is a big security hole. How do I disable this? I'm very new to web/PERL programming, so I'm not sure what other options I have. Any pointers are greatly appreciated. Thanks for your time and help.