“You must compile individual stylesheets from the

Question

I've installed Zurb Foundation sass into an expressionengine project but i'm getting this when saving the app.scss file:

Compass was unable to compile one or more files in the project:

You must compile individual stylesheets from the project directory.

All my paths are correct as they are the same as in another project that works fine.

Any idea what triggers that error so i can track down the issue?