diff --git a/SseServer/src/SseServer/Controllers/SseController.cs b/SseServer/src/SseServer/Controllers/SseController.cs
index f8a5a5d927..569a06bbb6 100644
--- a/SseServer/src/SseServer/Controllers/SseController.cs
+++ b/SseServer/src/SseServer/Controllers/SseController.cs
@@ -47,6 +47,8 @@ await _mediator.Send(new UpdateDeviceRegistrationCommand
         {
             _eventQueue.Register(address);
 
+            await streamWriter.SendServerSentEvent("ConnectionOpened");
+
             await foreach (var eventName in _eventQueue.DequeueFor(address, HttpContext.RequestAborted))
             {
                 await streamWriter.SendServerSentEvent(eventName);