Internet Explorer and .NET Framework 4.x Announcement

This post shares important information regarding support timelines for two empowering technologies—Internet Explorer and .NET Framework— to help you plan moving to the latest versions, where applicable, and ensure you take the necessary steps needed to become more secure and benefit from the latest releases.

The latest Internet Explorer browser offers many benefits such as improved security, additional speed, increased compatibility, and the ability to run the latest web sites and services, helping customers connect anytime, anywhere. Internet Explorer is core to enabling a mobile-first, cloud first world and we encourage customers to test and apply updates upon release for a more secure and improved user experience. For those not yet running the latest browser available for your operating system, we encourage you to migrate soon to take advantage of the latest security and functionality. 

Beginning January 12, 2016, only the most current version of Internet Explorer available for a supported operating system will receive technical support and security updates, as shown in the table below:


Windows Desktop and Server Operating Systems*

Internet Explorer Version

Windows Vista SP2

Internet Explorer 9

Windows 7 SP1

Internet Explorer 11

Windows 8.1 Update

Internet Explorer 11

Windows Server 2008 SP2

Internet Explorer 9

Windows Server 2008 R2 SP1

Internet Explorer 11

Windows Server 2012

Internet Explorer 10

Windows Server 2012 R2

Internet Explorer 11

* For more details on the support lifecycle, including the latest Windows Embedded operating system and Internet Explorer browser combinations, see the Microsoft Internet Explorer Support Lifecycle Policy Page.


If you are running on an older version of Internet Explorer, such as Internet Explorer 8 on Windows 7 SP1, we recommend you plan your migration to one of the above supported operating system and browser combinations by January 12, 2016. Microsoft offers many online support resources to help you upgrade to a current version, as well as a number of deployment and compatibility services available to assist with migrations. You can visit the Internet Explorer Blog, which includes guidance and upgrade resources.


We are especially sensitive to your needs to ensure existing web applications that were developed for previous versions of Internet Explorer, such as Internet Explorer 8, continue working while also ensuring you benefit from the latest and most secure version of Internet Explorer. In order to ease the migration of applications to current web standards, Enterprise Mode for Internet Explorer 11, released in April 2014, offers better backward compatibility and enables you to run many legacy web applications once you upgrade to a more modern browser. Microsoft is committed to supporting Enterprise Mode through the duration of the operating system lifecycle and continuing to improve Enterprise Mode backward compatibility, helping customers extend existing web application investments as needed. As an example, Windows 7 SP1 running Internet Explorer with Enterprise Mode will be supported through January 14, 2020. Microsoft will also continue to invest in tools and other resources to help customers upgrade and stay up-to-date on the latest version of Internet Explorer.


Just as the latest Internet Explorer provides the best experience for customers, the .NET Framework does the same for developers or for applications built upon it. The latest .NET Framework, version 4.5.2, offers new workflow features, improved diagnostics, additional performance improvements, and provides a seamless update requiring no recompilation if upgrading from within the .NET 4.x family. If your company is using a version of .NET 4.x, beginning January 12, 2016 only .NET Framework 4.5.2 will continue receiving technical support and security updates. After this date, Microsoft will no longer support .NET 4, 4.5, or 4.5.1. There is no change to the support timelines for any other .NET Framework version, including .NET 3.5 SP1, which will continue to be supported for the duration of the operating system lifecycle. For more details on the .NET Framework support lifecycle, visit the Microsoft .NET Framework Blog Link or Microsoft .NET Support Lifecycle Policy page.


The innovation with Internet Explorer and .NET Framework is one step in helping customers take full advantage of a mobile-first and cloud-first world.