VS 2015 - Error CS0012
February 6, 2016
When debugging Windows 8.1 apps in C# or Visual Basic, DataTips may not show up when you hover over expressions.
In addition, evaluating expressions in the debugger windows can fail, returning an error message similar to this:
error CS0012: The type ‘Windows.UI.Core.Dispatcher’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘Windows.UI.winmd’…
To fix the issue, enable the legacy C# and VB expression evaluators.
toolsdotnet