diff --git a/Gruntfile.js b/Gruntfile.js
index d988db5..c08cc05 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -83,6 +83,9 @@
 
                 // Before generating any new files, remove any previously-created files.
                 clean: {
+                    options: {
+                        force: true
+                    },
                     tests: ['.tmp'],
                     install: ['lib']
                 },