Sometimes you will find issues with web pages after an upgrade to the web application. The browser may be using the older version of the web page from the browser cache.
First, try these steps below. If that doesn't work try the web site links below. They do a good job of explaining browser cache and have great examples.
Close down all open IE browsers.
Open the IE browser and navigate to the page.
Hold down the "Shift" key and press the "F5" key.
Now begin to work with the site to see if it performs correctly.
Browser Cache, Clearing It and Different Browsers:
http://www.refreshyourcache.com/en/cache/
Clearing IE 9 Browser Cache (Other versions too)
http://www.refreshyourcache.com/en/internet-explorer-9/