The new look and feel experience of IE 9 and other benefits I was enjoying were cut short as I started to encounter various problems during my day-to-day work. There are many web applications that are not fully compatible with the latest html standards and hence, I had to switch IE 9 to compatibility mode many times and in some case even to Software Rendering mode. The major setback is with web publication software such as, wordpress where some controls in the admin console do not function and prevent you from performing the most basic things. For example with wordpress the control to insert, edit or remove a hyperlink is completely dead while writing content and doing basic formatting in text boxes turned out to be an impossible task.
Switching IE 9 to compatibility mode may help you avoid some issues with content publishing systems and you can find Compatibility View in the Tools menu but you need to display the Tools menu first as this is hidden by default. To show the command bar you need to right click the topmost row next to the websites' tabs and select Command bar. Then from the Tools menu, select Compatibility View.
To enable Software Rendering Mode go to Internet Options in the Tools menu, and on the Advanced tab check the Use software rendering instead of GPU rendering box under the Accelerated graphics section. This option may show some graphics that were previously failing to load or causing rendering problems. Running IE 9 in Software rendering mode may result in performance degradation and Microsoft recommends users to install the latest video driver that supports GPU hardware acceleration, and switch to IE 9 native GPU hardware acceleration.