Sometimes the website you’re visiting doesn’t look right. It shows up as a jumble of out-of-place menus, images, and text boxes. What’s going on? One possible explanation: The site might have been designed for an earlier version of Internet Explorer. If Internet Explorer recognizes that the webpage isn’t compatible, you’ll see the Compatibility View button on the Address bar. Try clicking it.
The Compatibility View button
In Compatibility View, websites will be displayed as if you were viewing them in a previous version of Internet Explorer, which will often correct display problems. You don’t need to click the button for a site after you’ve done it once—the next time you visit the site, Internet Explorer 9 will automatically show it in Compatibility View. (If you ever want to go back to browsing with Internet Explorer 9 on that site, just click the Compatibility View button again.)
This will drive you nuts. It raises a question about whether to warn the user to upgrade their browser in cases where they are just using compat mode in IE. Conditional directives don’t detect the case where the user is running IE9 and in compatibility mode (emulating IE7).