A method of controlling a browser window is disclosed. The method comprises the steps of associating the browser window to a token indicative of a personalized session; and repetitively, verifying said token; and, closing the browser window in dependence of said token. A valid token is generated at startup of the personalized session. The token is invalidated when the user logoffs from the personalized session. Upon detection of an invalid token all browser windows associated with said personalized session will be closed.