diff --git a/lib/decompress-zip.js b/lib/decompress-zip.js
index db0f8d1..73c9df6 100644
--- a/lib/decompress-zip.js
+++ b/lib/decompress-zip.js
@@ -238,14 +238,16 @@ DecompressZip.prototype.extractFiles = function (files, options, results) {
 
     results = results || [];
     var fileIndex = 0;
-    files.forEach(function (file) {
-        var promise = self.extractFile(file, options)
-        .then(function (result) {
-            self.emit('progress', fileIndex++, files.length);
-            results.push(result);
-        });
-
-        promises.push(promise);
+    files.filter(function (file) {
+            return file;
+        }).forEach(function (file) {
+            var promise = self.extractFile(file, options)
+            .then(function (result) {
+                self.emit('progress', fileIndex++, files.length);
+                results.push(result);
+            });
+    
+            promises.push(promise);
     });
 
     return Q.all(promises)