Version 1.1 is the first minor .NET Framework upgrade. It is available on its own as a [[Freely redistributable software|redistributable package]] or in a [[software development kit]], and was publishedoriginally released on 39 April 2003. It is also part of the second release of [[Visual Studio .NET 2003]]. This is the first version of the .NET Framework to be included as part of the Windows operating system, shipping with [[Windows Server 2003]]. Mainstream support for .NET Framework 1.1 ended on 14 October 2008, and extended support ended on 8 October 2013. .NET Framework 1.1 provides full [[backward compatibility]] to version 1.0, except in rare instances where an application will not run because it checks the version number of a library.<ref>{{cite web|title=.NET Framework Developer Center – Frequently Asked Questions |url=http://msdn.microsoft.com/en-us/netframework/Aa497323.aspx |archive-url=https://web.archive.org/web/20120724012426/http://msdn.microsoft.com/en-us/netframework/aa497323.aspx |archive-date=24 July 2012 |url-status=live}}</ref>
Changes in 1.1 include:<ref>{{cite web|title=New and Enhanced Features|url=https://msdn.microsoft.com/en-us/library/h88tthh0(v=vs.71).aspx|website=[[MSDN]]|publisher=[[Microsoft]]|archive-url=https://web.archive.org/web/20110127162056/http://msdn.microsoft.com/en-us/library/h88tthh0(v=vs.71).aspx|archive-date=27 January 2011 |url-status=live}}</ref>
