.NET 3.0 and 3.5 Died, Upgrade to .NET 4.0 or 3.5 SP1

Microsoft will kill support for both .NET Framework 3.0 and .NET framework 3.5 on April 12, 2010, which leaves customers with less than a year to upgrade. Microsoft's strong recommendation is that all migration processes be completed by April 12th, next year, with two options available, either .NET Framework 3.5 SP1 or the freshly released .NET Framework 4.0 RTM. "We are ending support for earlier iterations of .NET 3.0 and 3.5—but are giving customers a year to migrate before ending support. We will require all customers to be on .NET Framework 3.5 SP1 or later, by April 12th, 2011 in order to obtain security updates or support," Microsoft's David Carrington revealed.

At the same time, the decision to cut off support for .NET 3.0 and 3.5 on April 12, 2011 is part of a company move designed to overhaul how .NET Framework is supported. Essentially, the .NET Framework will no longer be treated as a standalone major product in terms of support, but instead it will become intimately connected with the Windows operating system. Of course, this is valid for versions 3.5 SP1, 4.0 and the successor of .NET Framework 4.0 going forward.

Reference: http://news.softpedia.com/news/NET-3-0-and-3-5-Die-April-12-2011-Upgrade-to-NET-4-0-or-3-5-SP1-141137.shtml