Enforce Compile Time Detection of Code Contracts in VB.NET Project

I'm trying to setup Code Contracts in a VB.NET project.

Here's a real simple method that should ensure that the passed in divisor argument is not zero:

<!-- language: lang-vb -->

Public Function Divide(ByVal numerator As Integer, ByVal divisor As Integer) As Double
    Contract.Requires(Of ArgumentOutOfRangeException)(divisor <> 0, "Divide By Zero Not Allowed")
    Return numerator / divisor
End Function

If I call Divide(5, 0), I should get a compile time error. But alas, I don't:

I've downloaded the Add-In from the **Visual Studio Gallery**.
I have static code analysis enabled on the Code Contracts Property Page:

This works when I follow the same steps in C#:

What else could be missing?