Clearing cookies using Developer Tools FOR MX5 (5.1.x and later) - Open the Developer Tools (F12)- Go to the Application tab, click the Clear storage item. - Ensure at least the Cookies option is selected in the right pane. - Click the Clear site data button. - You can also right-click on the site address under Storage > Cookies and select Clear.     FOR MX4.9 (and early MX5 versions) - Open the Developer Tools (F12)- Go to the Resources tab,