High Quality Content by WIKIPEDIA articles! Windows Internet Explorer 9 (IE9) is a version of the Internet Explorer web browser from Microsoft. It was released to the public on March 14, 2011. Microsoft has released Internet Explorer 9 as a major out-of-band version that is not tied to the release schedule of any particular version of Windows, unlike previous versions. It is the first version since Internet Explorer 2 to not be bundled with a Windows operating system, although some OEMs have installed it with Windows 7 on their PCs, as well as new Windows 7 laptops.