diff --git a/Source/Modules/AppDelegate.swift b/Source/Modules/AppDelegate.swift
index 93702611..40cbc575 100644
--- a/Source/Modules/AppDelegate.swift
+++ b/Source/Modules/AppDelegate.swift
@@ -74,7 +74,7 @@ class AppDelegate: NSObject, NSApplicationDelegate, ctlNonModalAlertWindowDelega
     mgrPrefs.setMissingDefaults()
 
     // 只要使用者沒有勾選檢查更新、沒有主動做出要檢查更新的操作，就不要檢查更新。
-    if UserDefaults.standard.object(forKey: VersionUpdateApi.kCheckUpdateAutomatically) != nil {
+    if mgrPrefs.checkUpdateAutomatically {
       checkForUpdate()
     }
   }
@@ -113,7 +113,7 @@ class AppDelegate: NSObject, NSApplicationDelegate, ctlNonModalAlertWindowDelega
 
     // time for update?
     if !forced {
-      if UserDefaults.standard.bool(forKey: VersionUpdateApi.kCheckUpdateAutomatically) == false {
+      if !mgrPrefs.checkUpdateAutomatically {
         return
       }
       let now = Date()