If this happens, try the following:

1) Press the logout link and close the browser.
2) Open a new browser window, and see if you’re still logged in.
3) If so, go to Tools–>Internet Options on your browser, and press the “Delete Cookies” button under Temporary Internet Files. Say okay, and close the browser
4) Open a new browser window and see if you’re still logged in.

When you login to the site, a cookie is placed on your computer. We have no control over that as it is all on your end, and there is nothing we can do if the site won’t log you out — you must play with your browser settings to make it work.