When accessing Email Insights you will notice that data may not be loading and the page rendering looks strange. Read through the following topic if you are experiencing vdata error.
This is caused by using Compatibility Mode in Internet Explorer. It prevents the browser from running Angular scripts. While Internet Explorer 9 is still technically supported, we recommend using Google Chrome or Mozilla Firefox. Both browsers are supported up to their latest versions.
To check if Compatibility Mode is turned on or off: Look in the address bar (URL bar). On the right side of the address bar find the icon that looks like a torn piece of paper. If this icon is grey, Compatibility Mode is turned off. If it's blue, then it's turned on.
To turn off Compatibility Mode: Click on the icon. This will refresh the page and turn off Compatibility Mode.