diff --git a/Wox/ActionKeywords.xaml.cs b/Wox/ActionKeywords.xaml.cs
index 2dc0e02bd1..c86671c6ef 100644
--- a/Wox/ActionKeywords.xaml.cs
+++ b/Wox/ActionKeywords.xaml.cs
@@ -40,6 +40,7 @@ namespace Wox
         {
             var oldActionKeyword = _plugin.Metadata.ActionKeywords[0];
             var newActionKeyword = tbAction.Text.Trim();
+            newActionKeyword = newActionKeyword.Length > 0 ? newActionKeyword : "*";
             if (!PluginManager.ActionKeywordRegistered(newActionKeyword))
             {
                 var id = _plugin.Metadata.ID;