Can't add LINQ to SQL Classes in project upgraded to 3.5

Question

I just upgraded a project to 3.5 SP1 and trying to add a LINQ to SQL class item to the project and can't as it doesn't appear in the Add Item list.

Though if i create a new project in the same solution and try adding it the item (LINQ to SQL classes) is available and I can add it to the project.

What do i have to do to be able to add LINQ to SQL classes to my existing/upgraded project?

Answer 1

Right click the project, go to properties, and make sure you have the project set to target the correct version of the framework.

Edit To clarify, you can "upgrade" a project through Visual Studio but it can still be set to target an older version of .NET.