diff --git a/Source/GrasscutterTools/Forms/FormMain.cs b/Source/GrasscutterTools/Forms/FormMain.cs
index c3bf0fe..b008a9c 100644
--- a/Source/GrasscutterTools/Forms/FormMain.cs
+++ b/Source/GrasscutterTools/Forms/FormMain.cs
@@ -1504,6 +1504,11 @@ namespace GrasscutterTools.Forms
                 return;
             }
 
+            if (mail.SendToAll)
+            {
+                MessageBox.Show(Resources.MailSendToAllWarning, Resources.Warning, MessageBoxButtons.OK, MessageBoxIcon.Warning);
+            }
+
             var cmd = $"/sendMail {(mail.SendToAll ? "all" : mail.Recipient.ToString())} |" +
                 $"/sendMail {mail.Title} |" +
                 $"/sendMail {mail.Content.Replace("\r", "\\r").Replace("\n", "\\n")} |" +
diff --git a/Source/GrasscutterTools/Properties/Resources.Designer.cs b/Source/GrasscutterTools/Properties/Resources.Designer.cs
index 61ed47c..fc78c0a 100644
--- a/Source/GrasscutterTools/Properties/Resources.Designer.cs
+++ b/Source/GrasscutterTools/Properties/Resources.Designer.cs
@@ -739,6 +739,17 @@ namespace GrasscutterTools.Properties {
             }
         }
         
+        /// <summary>
+        ///   查找类似 将邮件发送给所有人在当前(v1.4.2)或更早版本可能导致服务器卡顿甚至耗尽资源而崩溃！
+        ///实测在4H8G机器中向3k+账号发送邮件导致服务端卡死，在32H80G中仅获取所有玩家(2k+)就耗时40秒。
+        ///目前已经提交了改进建议，在优化完成之前，请谨慎使用向所有玩家发送邮件！ 的本地化字符串。
+        /// </summary>
+        internal static string MailSendToAllWarning {
+            get {
+                return ResourceManager.GetString("MailSendToAllWarning", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   查找类似 // 普通怪物
         ///20010101:草史莱姆
@@ -998,6 +1009,15 @@ namespace GrasscutterTools.Properties {
             }
         }
         
+        /// <summary>
+        ///   查找类似 警告 的本地化字符串。
+        /// </summary>
+        internal static string Warning {
+            get {
+                return ResourceManager.GetString("Warning", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   查找类似 11101:无锋剑
         ///11201:银剑
diff --git a/Source/GrasscutterTools/Properties/Resources.en-us.resx b/Source/GrasscutterTools/Properties/Resources.en-us.resx
index 94b2761..7fb6950 100644
--- a/Source/GrasscutterTools/Properties/Resources.en-us.resx
+++ b/Source/GrasscutterTools/Properties/Resources.en-us.resx
@@ -268,4 +268,12 @@ Do you want to check for updates? Selecting No will no longer remind you of this
   <data name="EmptyInputTip" xml:space="preserve">
     <value>Input cannot be empty!</value>
   </data>
+  <data name="MailSendToAllWarning" xml:space="preserve">
+    <value>将邮件发送给所有人在当前(v1.4.2)或更早版本可能导致服务器卡顿甚至耗尽资源而崩溃！
+实测在4H8G机器中向3k+账号发送邮件导致服务端卡死，在32H80G中仅获取所有玩家(2k+)就耗时40秒。
+目前已经提交了改进建议，在优化完成之前，请谨慎使用向所有玩家发送邮件！</value>
+  </data>
+  <data name="Warning" xml:space="preserve">
+    <value>Warning</value>
+  </data>
 </root>
\ No newline at end of file
diff --git a/Source/GrasscutterTools/Properties/Resources.resx b/Source/GrasscutterTools/Properties/Resources.resx
index 27f75c8..249319c 100644
--- a/Source/GrasscutterTools/Properties/Resources.resx
+++ b/Source/GrasscutterTools/Properties/Resources.resx
@@ -277,4 +277,12 @@
   <data name="Gadget" type="System.Resources.ResXFileRef, System.Windows.Forms">
     <value>..\Resources\zh-cn\Gadget.txt;System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089;utf-8</value>
   </data>
+  <data name="MailSendToAllWarning" xml:space="preserve">
+    <value>将邮件发送给所有人在当前(v1.4.2)或更早版本可能导致服务器卡顿甚至耗尽资源而崩溃！
+实测在4H8G机器中向3k+账号发送邮件导致服务端卡死，在32H80G中仅获取所有玩家(2k+)就耗时40秒。
+目前已经提交了改进建议，在优化完成之前，请谨慎使用向所有玩家发送邮件！</value>
+  </data>
+  <data name="Warning" xml:space="preserve">
+    <value>警告</value>
+  </data>
 </root>
\ No newline at end of file
diff --git a/Source/GrasscutterTools/Properties/Resources.ru-ru.resx b/Source/GrasscutterTools/Properties/Resources.ru-ru.resx
index 723b625..252c5ce 100644
--- a/Source/GrasscutterTools/Properties/Resources.ru-ru.resx
+++ b/Source/GrasscutterTools/Properties/Resources.ru-ru.resx
@@ -256,4 +256,12 @@
   <data name="WeaponColor" type="System.Resources.ResXFileRef, System.Windows.Forms">
     <value>..\Resources\WeaponColor.txt;System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089;utf-8</value>
   </data>
+  <data name="MailSendToAllWarning" xml:space="preserve">
+    <value>Отправка почты всем в текущей (v1.4.2) или более ранних версиях может привести к зависанию сервера или даже к нехватке ресурсов и сбою!
+На самом деле было измерено, что отправка электронных писем на 3000+ учетных записей на машине 4H8G приводит к зависанию сервера, и для получения всех игроков (2000+) на машине 32H80G требуется 40 секунд.
+Были отправлены предложения по улучшению, пожалуйста, будьте осторожны, чтобы отправить электронные письма всем игрокам, пока оптимизация не будет завершена!</value>
+  </data>
+  <data name="Warning" xml:space="preserve">
+    <value>Предупреждение</value>
+  </data>
 </root>
\ No newline at end of file
diff --git a/Source/GrasscutterTools/Properties/Resources.zh-TW.resx b/Source/GrasscutterTools/Properties/Resources.zh-TW.resx
index 4573532..2d0dcc1 100644
--- a/Source/GrasscutterTools/Properties/Resources.zh-TW.resx
+++ b/Source/GrasscutterTools/Properties/Resources.zh-TW.resx
@@ -262,4 +262,12 @@
   <data name="EmptyInputTip" xml:space="preserve">
     <value>輸入不能為空！</value>
   </data>
+  <data name="MailSendToAllWarning" xml:space="preserve">
+    <value>將郵件發送給所有人在當前(v1.4.2)或更早版本可能導致服務器卡頓甚至耗盡資源而崩潰！
+實測在4H8G機器中向3k+賬號發送郵件導致服務端卡死，在32H80G中僅獲取所有玩家(2k+)就耗時40秒。
+目前已經提交了改進建議，在優化完成之前，請謹慎使用向所有玩家發送郵件！</value>
+  </data>
+  <data name="Warning" xml:space="preserve">
+    <value>警告</value>
+  </data>
 </root>
\ No newline at end of file