diff --git a/alpha/help/Command_ShlExt.txt b/alpha/help/Command_ShlExt.txt
index 5baf98e..fe1e5e5 100644
--- a/alpha/help/Command_ShlExt.txt
+++ b/alpha/help/Command_ShlExt.txt
@@ -22,6 +22,7 @@ regsvr32.exe /u MultiParShlExt64.dll
 
  You can put a key for Shell Extension DLL,
 which key name is "ShellExtension" under [Option] section.
+You need to restart Windows Explorer for refresh, when you changed the value.
 The default value is 0, when the key doesn't exist.
 
  The value consists in multiple bit.