diff --git a/lib/EAPBase/include/Module.h b/lib/EAPBase/include/Module.h
index eaf4d47..a20132d 100644
--- a/lib/EAPBase/include/Module.h
+++ b/lib/EAPBase/include/Module.h
@@ -781,7 +781,7 @@ namespace eap
         virtual void set_response_attributes(
             _In_       EAP_SESSION_HANDLE  hSession,
             _In_ const EapAttributes       *pAttribs,
-            _Inout_    EapPeerMethodOutput *pEapOutput) = 0;
+            _Out_      EapPeerMethodOutput *pEapOutput) = 0;
 
         /// @}
     };
diff --git a/lib/TTLS/include/Module.h b/lib/TTLS/include/Module.h
index edcc02a..5689f9e 100644
--- a/lib/TTLS/include/Module.h
+++ b/lib/TTLS/include/Module.h
@@ -209,7 +209,7 @@ namespace eap
         virtual void set_response_attributes(
             _In_       EAP_SESSION_HANDLE  hSession,
             _In_ const EapAttributes       *pAttribs,
-            _Inout_    EapPeerMethodOutput *pEapOutput);
+            _Out_      EapPeerMethodOutput *pEapOutput);
 
         /// @}
 
diff --git a/lib/TTLS/src/Module.cpp b/lib/TTLS/src/Module.cpp
index 206eab5..df65d3f 100644
--- a/lib/TTLS/src/Module.cpp
+++ b/lib/TTLS/src/Module.cpp
@@ -334,9 +334,9 @@ void eap::peer_ttls::get_response_attributes(
 
 
 void eap::peer_ttls::set_response_attributes(
-            _In_       EAP_SESSION_HANDLE  hSession,
-            _In_ const EapAttributes       *pAttribs,
-            _Inout_    EapPeerMethodOutput *pEapOutput)
+    _In_       EAP_SESSION_HANDLE  hSession,
+    _In_ const EapAttributes       *pAttribs,
+    _Out_      EapPeerMethodOutput *pEapOutput)
 {
     UNREFERENCED_PARAMETER(hSession);
     UNREFERENCED_PARAMETER(pAttribs);