I\'ve set up Web Essentials 2013 (in Visual Studio 2012) and loaded in the default Twitter Bootstrap LESS source files. Auto-build and minification is working perfectly, exc
For ignoring only files, you can use underscore at the file name.
Web Essentials has an internal convention whereby files beginning with an underscore will not be saved to CSS.
This is actually quite useful. You don’t want your variables.less or mixins.less files being saved as variables.css or mixins.css. So in this case, name them _variables.less and _mixins.less. They will be compiled (and thus checked for correct syntax) but won’t take up space on disk or in source control as redundant CSS files.
https://medium.com/@brendaningram/web-essentials-not-saving-css-files-a450b8c2d23a