diff --git a/S7.Net/PlcAsynchronous.cs b/S7.Net/PlcAsynchronous.cs
index b6b49c6..42b61a7 100644
--- a/S7.Net/PlcAsynchronous.cs
+++ b/S7.Net/PlcAsynchronous.cs
@@ -35,6 +35,7 @@ namespace S7.Net
             catch(Exception)
             {
                 stream.Dispose();
+                throw;
             }
         }