The document cannot be opened. It has been renamed, deleted or moved.

1. In the Individual components section of the Visual Studio Installer, make sure that Razor Language Services is checked.
2. After installation, make sure that Razor Language Services is enabled in the Installed section of Extensions and Updates dialog.
3. Restart Visual Studio.

I also installed the Advanced ASP.NET features in the installer, but I don't know how much of an effect it has on this issue.

 

https://developercommunity.visualstudio.com/content/problem/194267/the-document-cannot-be-opened-it-has-been-renamed.html