If you find such a thing, then you need to uninstall that Internet Explorer 9. So you need to go to the Control Panel, click Uninstall a Program, then go to third party software listing and in Installed Updates. First, check if there is a listed previously build of Internet Explorer. The main reason for this problem is that, there is a beta, a preview build or release candidate build of Internet Explorer 9 that is currently installed on your computer, which prevents the final version installation. What I've known is that Microsoft has released their final version of Internet Explorer 9 and that some users may experience this kind of error when they try to run it. IE9 Error on Upgrading: Setup cannot continue
