Hello, We have investigated further the issue caused by Blend 2015 and reported it to Microsoft. You could find the logged item on the following link: https://connect.microsoft.com/VisualStudio/feedback/details/3110921/blend-2015-does-not-load-the-custom-design-time-assembly-that-uses-the-expression-naming-convention As soon as we have some more information we will post it here as well. Regards, Nasko
sad that blend is dead for WPF development. bug is active almost a year...