diff --git a/Services/ClientConfigService.cs b/Services/ClientConfigService.cs
index f4770a2..8fa16ee 100644
--- a/Services/ClientConfigService.cs
+++ b/Services/ClientConfigService.cs
@@ -66,8 +66,23 @@ public sealed class ClientConfigService : IConfigService
         SaveConfig();
     }
 
-    public string GetDeviceId() => _config.DeviceId ?? string.Empty;
-    public void SetDeviceId(string deviceId) { _config.DeviceId = deviceId ?? string.Empty; SaveConfig(); }
+    public string GetDeviceId()
+    {
+        if (!string.IsNullOrWhiteSpace(_config.DeviceId))
+            return _config.DeviceId.Trim();
+
+        _config.DeviceId = ResolveMachineDeviceId();
+        SaveConfig();
+        return _config.DeviceId;
+    }
+
+    public void SetDeviceId(string deviceId)
+    {
+        _config.DeviceId = string.IsNullOrWhiteSpace(deviceId)
+            ? ResolveMachineDeviceId()
+            : deviceId.Trim();
+        SaveConfig();
+    }
 
     public bool GetRememberAdminCredentials() => _config.RememberAdminCredentials;
     public void SetRememberAdminCredentials(bool remember) { _config.RememberAdminCredentials = remember; SaveConfig(); }
@@ -133,6 +148,14 @@ public sealed class ClientConfigService : IConfigService
         }
     }
 
+    private static string ResolveMachineDeviceId()
+    {
+        var machineName = Environment.MachineName;
+        return string.IsNullOrWhiteSpace(machineName)
+            ? Guid.NewGuid().ToString("N")
+            : machineName.Trim();
+    }
+
     private static string EncryptPassword(string plain)
     {
         if (string.IsNullOrEmpty(plain)) return string.Empty;
diff --git a/UtopiaCanteen.Client/App.xaml.cs b/UtopiaCanteen.Client/App.xaml.cs
index d444887..bf98d68 100644
--- a/UtopiaCanteen.Client/App.xaml.cs
+++ b/UtopiaCanteen.Client/App.xaml.cs
@@ -34,7 +34,10 @@ public partial class App : Application
         }
 
         var configService = new ClientConfigService();
-        FileLogger.Info("ClientApp", $"Backend base URL={configService.GetBackendBaseUrl()}");
+        FileLogger.Info("ClientApp", $"BackendBaseUrl = {configService.GetBackendBaseUrl()}");
+        FileLogger.Info(
+            "ClientApp",
+            $"Device ID resolved. MachineName={Environment.MachineName}, DeviceId={configService.GetDeviceId()}");
         FileLogger.Info("ClientApp", $"Logs directory={LogPaths.ClientLogsDirectory}");
 
         var httpClient = new HttpClient { Timeout = TimeSpan.FromMinutes(5) };