diff --git a/src/System.Windows.Forms.Design/src/System/ComponentModel/Design/CodeMarkers.cs b/src/System.Windows.Forms.Design/src/System/ComponentModel/Design/CodeMarkers.cs
index 67a83d0662f..f85dcbc09ff 100644
--- a/src/System.Windows.Forms.Design/src/System/ComponentModel/Design/CodeMarkers.cs
+++ b/src/System.Windows.Forms.Design/src/System/ComponentModel/Design/CodeMarkers.cs
@@ -393,7 +393,7 @@ public bool InitPerformanceDll(int iApp, string strRegRoot, RegistryView registr
 
             if (strRegRoot == null)
             {
-                throw new ArgumentNullException(nameof(strRegRoot");
+                throw new ArgumentNullException(nameof(strRegRoot));
             }
             
             this.regroot = strRegRoot;