Proper way to initialize a C# dictionary with values

I am creating a dictionary in a C# file with the following code:

private readonly Dictionary FILE_TYPE_DICT
        = new Dictionary
        {
            {"csv", XlFileFormat.xlCSV},
            {"html", XlFileFormat.xlHtml}
        };

There is a red line under new with the error:

Feature 'collection initilializer' cannot be used because it is not part of the ISO-2 C# language specification

What is going on here?

I am using .NET version 2.

I can't reproduce this issue in a simple .NET 4.0 console application:

static class Program
{
    static void Main(string[] args)
    {
        var myDict = new Dictionary
        {
            { "key1", "value1" },
            { "key2", "value2" }
        };

        Console.ReadKey();
    }
}

Can you try to reproduce it in a simple Console application and go from there? It seems likely that you're targeting .NET 2.0 (which doesn't support it) or client profile framework, rather than a version of .NET that supports initialization syntax.

Stack Overflow Q#17047602, score: 1246