Microsoft has been aggressively updating Visual Studio 2017 this year; since its introduction last spring there have been five major updates. This update pace can't help but ultimately cause problems if you don't keep your copy updated.
Recently, some using Visual Studio 2017 report seeing this error:
Error: Could not load file or assembly "Microsoft.VisualStudio.AppDesigner. version= 126.96.36.199"
This error isn't with ASNA products, but rather it's occurring because of Visual Studio version issues. Click the blue button below to read how to resolve this issue.