VS2015 View Designer/View Code on XAML Pages gives Error

I have the latest Xamarin 3.11.836 installed on Win10 with VS2015 and when I have a XAML file open, I expect View Code to open the CS file and when in the CS file of a Page I expect View Designer to open the XAML. However I am getting the same error in both instances.

"There is no editor available for . Make sure the application for the file type (.xaml) is installed."

Clicking the appropriate file opens the CS or XAML as expected, anyone else seeing this? Is it a bug or just a problem with my system?

Thought I would ask here before reporting it as a bug and see if others are seeing the same behavior.

Thanks
M