I'm trying to add a WPF ResourceDictionary to a C# project that was created a while ago. The project was not originally a WPF project, but now I need to include some WPF resources in it.

When I right click the project and select "Add", ResourceDictionary is not an option. Even if I open the Modal dialog box and navigate to where the ResourceDictionary type should be (along side the other WPF types), it is not present.

Also, when I manually add a XAML file that has ResourceDictionary syntax to the project, I can't programmatically load it using WPF Application.Load(uri) syntax, so I feel VS2010 is preventing me from adding the file for a reason.

How can I make my project "able" to have a ResourceDictionary added without recreating the entire project from scratch as a WPF project and re-adding every file from scratch?

Additionally, what defines the file types that can be added to projects so I can avoid similar problems in the future? Hopefully it's something simple like a line I need to add to my AssemblyInfo.cs file.

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