I hope some one has seen this behavior before, because I am stumped.Whenever I try to open any CSS file all I get is: This operation could not be completed ...

Check your CSS code without leaving the IDE by using CssCop, which brings the CSS Lint functionality to the Visual Studio environment.

CSS mirror editing is a feature of the Microsoft Edge DevTools extension that works around that problem. Any change that you make in the **Styles** tab also automatically changes the `.css` file in ...

You're just one click away from using Windows Explorer with the files in your project or the individual file in your editor window.