diff --git a/builder/virtualbox/common/driver_4_2.go b/builder/virtualbox/common/driver_4_2.go
index 8af782947..9bfa3baf1 100644
--- a/builder/virtualbox/common/driver_4_2.go
+++ b/builder/virtualbox/common/driver_4_2.go
@@ -24,7 +24,7 @@ func (d *VBox42Driver) CreateSATAController(vmName string, name string, portcoun
 		return err
 	}
 
-	portCountArg = "--portcount"
+	portCountArg := "--portcount"
 	if strings.HasPrefix(version, "0.") || strings.HasPrefix(version, "1.") || strings.HasPrefix(version, "2.") ||
 		strings.HasPrefix(version, "3.") || strings.HasPrefix(version, "4.0") || strings.HasPrefix(version, "4.1") ||
 		strings.HasPrefix(version, "4.2") {