diff --git a/Class/AsyncTcpServer.cs b/Class/AsyncTcpServer.cs
index b184ad8..221a755 100644
--- a/Class/AsyncTcpServer.cs
+++ b/Class/AsyncTcpServer.cs
@@ -4,6 +4,7 @@ using System.Data;
 using System.Security.Cryptography.Pkcs;
 using System.Text;
 using System.Text.Json;
+using System.Threading.Channels;
 using System.Windows;
 using System.Windows.Markup;
 using System.Xml.Linq;
@@ -38,17 +39,17 @@ namespace ForwardingServerUI.Class
                 //离线记录
                 Console.WriteLine("[" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff") + "] NOT ID " +
                     client.Id + " IP " + client.IP);
-
-                DataRow row = MainWindowViewModel._machineTable.Select("ID='" + client.Id + "'").First();
-
-                Console.WriteLine("[" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff") + "] BREAK LINK ID = " +
-                      row["ID"] + " IP = " + row["IP"] + " Enterprise = " + row["Enterprise"] +
-                      " MachineName = " + row["MachineName"]);
-
                 Application.Current.Dispatcher.Invoke(() =>
                 {
+                    DataRow row = MainWindowViewModel._machineTable.Select("ID='" + client.Id + "'").First();
+
+                    Console.WriteLine("[" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff") + "] BREAK LINK ID = " +
+                          row["ID"] + " IP = " + row["IP"] + " Enterprise = " + row["Enterprise"] +
+                          " MachineName = " + row["MachineName"]);
+
                     MainWindowViewModel._machineTable.Rows.Remove(row);
                 });
+
                 return EasyTask.CompletedTask;
             };//有客户端断开连接
             service.Received = (client, e) =>{                
@@ -162,43 +163,49 @@ namespace ForwardingServerUI.Class
         {
             try
             {
-                int rows = MainWindowViewModel._machineTable.Rows.Count;
-                for (int i = rows; i > 0; i--)
-                {
-                    DataRow dataRow = MainWindowViewModel._machineTable.Rows[i-1];
-                    DateTime dateTime = DateTime.Parse(dataRow["HeartbeatTime"].ToString()!);
+                DataRow[] row = MainWindowViewModel._machineTable.Select("HeartbeatTime<'" + DateTime.Now.AddSeconds(-30).ToString() + "'");
 
-                    if (DateTime.Now > dateTime.AddSeconds(30) && (int)dataRow["Start"] == 30)
+                Application.Current.Dispatcher.Invoke(() =>
+                {
+                    foreach (var dataRow in row)
                     {
-                        Application.Current.Dispatcher.Invoke(() =>
+                        if ((int)dataRow["Start"] == 30)
                         {
                             dataRow.BeginEdit();
                             dataRow["Start"] = 999;
                             dataRow.EndEdit();
                             dataRow.AcceptChanges();
-                        });
 
-                        Console.WriteLine("[" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff") + "] NOT LINK ID = " +
-                            dataRow["ID"] + " IP = " + dataRow["IP"] + " Enterprise = " + dataRow["Enterprise"] +
-                            " MachineName = " + dataRow["MachineName"]);
+                            Console.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] NOT LINK ID = {dataRow["ID"]} " +
+                                              $"IP = {dataRow["IP"]} Enterprise = {dataRow["Enterprise"]} " +
+                                              $"MachineName = {dataRow["MachineName"]}");
+                        }
                     }
+                });
 
-                    if (DateTime.Now > dateTime.AddSeconds(180))
+                DataRow[] rowout = MainWindowViewModel._machineTable.Select("HeartbeatTime<'" + DateTime.Now.AddSeconds(-120).ToString() + "'");
+
+                Application.Current.Dispatcher.Invoke(() =>
+                {
+                    foreach (var dataRow in rowout)
                     {
-                        //关闭无回应连接
+                        dataRow.BeginEdit();
+                        dataRow["Start"] = 999;
+                        dataRow.EndEdit();
+                        dataRow.AcceptChanges();
+
                         foreach (var item in service.Clients)
                         {
                             if (item.Id == dataRow["ID"].ToString())
                             {
-                                await item.CloseAsync();
-
-                                //在断开连接后，释放对象。
-                                item.Dispose();
+                                item.CloseAsync(); // 关闭完成
+                                item.Dispose();          // 释放资源
+                                break;
                             }
                         }
                     }
-                 
-                }
+                });
+
             }
             catch (Exception ex)
             {
@@ -206,6 +213,6 @@ namespace ForwardingServerUI.Class
                 LogGing.ERRDATA(ex);
             }
         }
-
+             
     }      
 }
diff --git a/MainWindowViewModel.cs b/MainWindowViewModel.cs
index 9c8b36e..7a8f645 100644
--- a/MainWindowViewModel.cs
+++ b/MainWindowViewModel.cs
@@ -26,6 +26,8 @@ namespace ForwardingServerUI
         [ObservableProperty]
         public static DataTable _userTable = new();
 
+        public static readonly object TableLock = new object();
+
         public async void Data()
         {
             _machineTable.Columns.Add("ID", typeof(string));