diff --git a/lib/xenu_nntp/session.py b/lib/xenu_nntp/session.py
index c093800..61d171a 100644
--- a/lib/xenu_nntp/session.py
+++ b/lib/xenu_nntp/session.py
@@ -111,7 +111,7 @@ class Session(Connection):
 
         self.mode = SessionMode.READER
 
-        return self.respond(ResponseCode.NNTP_POST_PROHIBITED)
+        return self.respond(ResponseCode.NNTP_SERVICE_READY_POST_PROHIBITED)
 
     def _cmd_group(self, name: str):
         newsgroup = self.newsgroup_by_name(name)