Sharepoint 2007 and ASP.NET 4.0

Question

Is it possible to create ASP.NET 4.0 "_layouts" pages in Sharepoint 2007 (WSS or MOSS)?

Answer 1

You'd have to reconfigure the application pool of your Web app to use .NET 4, but this is not supported. Even SharePoint 2010 is on .NET 3.5.

Answer 2

Although it's not officially supported, I believe the situation is similar to using .net 3.5 on the earlier versions of SharePoint 2007 - it works with a bunch of changes to web.config, as all newer versions of .net support running 2.0 code.

That said though, you should test with a simple page before you commit to anything, and you're out of luck if you need to get it past corporate infrastructure people.

Answer 3

@Tom Clarkson

Although it is true that you can make web.config changes to a MOSS site in order to get it to work with ASP.NET 3.5, I am not sure that is the case with .NET 4.

ASP.NET 4.0 uses a new version of the CLR, unlike versions 2.0 -> 3.5. 3.5 is really just a marketing term and should probably have been named 2.x.