diff --git a/lib/netcore/Thrift/Transports/Client/TStreamClientTransport.cs b/lib/netcore/Thrift/Transports/Client/TStreamClientTransport.cs
index f7164f0..be2011e 100644
--- a/lib/netcore/Thrift/Transports/Client/TStreamClientTransport.cs
+++ b/lib/netcore/Thrift/Transports/Client/TStreamClientTransport.cs
@@ -82,7 +82,7 @@
             if (OutputStream == null)
             {
                 throw new TTransportException(TTransportException.ExceptionType.NotOpen,
-                    "Cannot read from null inputstream");
+                    "Cannot write to null outputstream");
             }
 
             await OutputStream.WriteAsync(buffer, offset, length, cancellationToken);