diff --git a/lib/TTLS/include/Method.h b/lib/TTLS/include/Method.h
index 66fb974..db362ee 100644
--- a/lib/TTLS/include/Method.h
+++ b/lib/TTLS/include/Method.h
@@ -141,9 +141,6 @@ namespace eap
         virtual void process_application_data(_In_bytecount_(size_msg) const void *msg, _In_ size_t size_msg);
 
     protected:
-        config_method_ttls &m_cfg;          ///< EAP-TTLS method configuration
-        credentials_ttls &m_cred;           ///< EAP-TTLS credentials
-
         #pragma warning(suppress: 4480)
         enum version_t :unsigned char {
             version_0 = 0,                  ///< EAP-TTLS v0
diff --git a/lib/TTLS/src/Method.cpp b/lib/TTLS/src/Method.cpp
index 437b9fa..1bb4806 100644
--- a/lib/TTLS/src/Method.cpp
+++ b/lib/TTLS/src/Method.cpp
@@ -29,8 +29,6 @@ using namespace winstd;
 //////////////////////////////////////////////////////////////////////
 
 eap::method_ttls::method_ttls(_In_ module &module, _In_ config_method_ttls &cfg, _In_ credentials_ttls &cred) :
-    m_cfg(cfg),
-    m_cred(cred),
     m_version(version_0),
     method_tls(module, cfg, cred)
 {
@@ -38,8 +36,6 @@ eap::method_ttls::method_ttls(_In_ module &module, _In_ config_method_ttls &cfg,
 
 
 eap::method_ttls::method_ttls(_Inout_ method_ttls &&other) :
-    m_cfg     (          other.m_cfg     ),
-    m_cred    (          other.m_cred    ),
     m_version (std::move(other.m_version)),
     m_inner   (std::move(other.m_inner  )),
     method_tls(std::move(other          ))
@@ -68,9 +64,9 @@ void eap::method_ttls::begin_session(
     method_tls::begin_session(dwFlags, pAttributeArray, hTokenImpersonateUser, dwMaxSendPacketSize);
 
     // Initialize inner method.
-    switch (m_cfg.m_inner->get_method_id()) {
-    case eap_type_legacy_pap     : m_inner.reset(new method_pap     (m_module, (config_method_pap     &)*m_cfg.m_inner, (credentials_pass     &)*m_cred.m_inner.get())); break;
-    case eap_type_legacy_mschapv2: m_inner.reset(new method_mschapv2(m_module, (config_method_mschapv2&)*m_cfg.m_inner, (credentials_pass&)*m_cred.m_inner.get())); break;
+    switch (dynamic_cast<config_method_ttls&>(m_cfg).m_inner->get_method_id()) {
+    case eap_type_legacy_pap     : m_inner.reset(new method_pap     (m_module, (config_method_pap     &)*dynamic_cast<config_method_ttls&>(m_cfg).m_inner, (credentials_pass&)*dynamic_cast<credentials_ttls&>(m_cred).m_inner.get())); break;
+    case eap_type_legacy_mschapv2: m_inner.reset(new method_mschapv2(m_module, (config_method_mschapv2&)*dynamic_cast<config_method_ttls&>(m_cfg).m_inner, (credentials_pass&)*dynamic_cast<credentials_ttls&>(m_cred).m_inner.get())); break;
     default: throw invalid_argument(__FUNCTION__ " Unsupported inner authentication method.");
     }
     m_inner->begin_session(dwFlags, pAttributeArray, hTokenImpersonateUser, MAXDWORD);
diff --git a/lib/TTLS_UI/include/TTLS_UI.h b/lib/TTLS_UI/include/TTLS_UI.h
index 0007799..3f19337 100644
--- a/lib/TTLS_UI/include/TTLS_UI.h
+++ b/lib/TTLS_UI/include/TTLS_UI.h
@@ -135,7 +135,6 @@ protected:
     /// \endcond
 
 protected:
-    eap::config_method_ttls &m_cfg;         ///< TTLS configuration
     wxStaticText *m_outer_title;            ///< Outer authentication title
     wxTTLSConfigPanel *m_outer_identity;    ///< Outer identity configuration panel
     wxTLSConfigPanel *m_tls;                ///< TLS configuration panel
diff --git a/lib/TTLS_UI/src/TTLS_UI.cpp b/lib/TTLS_UI/src/TTLS_UI.cpp
index c2bcfd1..42d9230 100644
--- a/lib/TTLS_UI/src/TTLS_UI.cpp
+++ b/lib/TTLS_UI/src/TTLS_UI.cpp
@@ -169,7 +169,6 @@ void wxTTLSConfigPanel::OnUpdateUI(wxUpdateUIEvent& event)
 //////////////////////////////////////////////////////////////////////
 
 wxTTLSConfigWindow::wxTTLSConfigWindow(eap::config_provider &prov, eap::config_method &cfg, wxWindow* parent) :
-    m_cfg((eap::config_method_ttls&)cfg),
     m_cfg_pap(cfg.m_module, cfg.m_level + 1),
     m_cfg_mschapv2(cfg.m_module, cfg.m_level + 1),
     wxEAPConfigWindow(prov, cfg, parent)
@@ -200,10 +199,10 @@ wxTTLSConfigWindow::wxTTLSConfigWindow(eap::config_provider &prov, eap::config_m
     m_outer_title->SetForegroundColour( wxSystemSettings::GetColour( wxSYS_COLOUR_INACTIVECAPTION ) );
     sb_content->Add(m_outer_title, 0, wxALL|wxALIGN_RIGHT, 5);
 
-    m_outer_identity = new wxTTLSConfigPanel(m_prov, m_cfg, this);
+    m_outer_identity = new wxTTLSConfigPanel(m_prov, dynamic_cast<eap::config_method_ttls&>(m_cfg), this);
     sb_content->Add(m_outer_identity, 0, wxALL|wxEXPAND, 5);
 
-    m_tls = new wxTLSConfigPanel(m_prov, m_cfg, this);
+    m_tls = new wxTLSConfigPanel(m_prov, dynamic_cast<eap::config_method_tls&>(m_cfg), this);
     sb_content->Add(m_tls, 0, wxALL|wxEXPAND, 5);
 
     wxSize size = sb_content->CalcMin();
@@ -232,14 +231,14 @@ wxTTLSConfigWindow::~wxTTLSConfigWindow()
 
 bool wxTTLSConfigWindow::TransferDataToWindow()
 {
-    switch (m_cfg.m_inner->get_method_id()) {
+    switch (((eap::config_method_ttls&)m_cfg).m_inner->get_method_id()) {
     case winstd::eap_type_legacy_pap:
-        m_cfg_pap = *(eap::config_method_pap*)m_cfg.m_inner.get();
+        m_cfg_pap = *(eap::config_method_pap*)((eap::config_method_ttls&)m_cfg).m_inner.get();
         m_inner_type->SetSelection(0); // 0=PAP
         break;
 
     case winstd::eap_type_legacy_mschapv2:
-        m_cfg_mschapv2 = *(eap::config_method_mschapv2*)m_cfg.m_inner.get();
+        m_cfg_mschapv2 = *(eap::config_method_mschapv2*)((eap::config_method_ttls&)m_cfg).m_inner.get();
         m_inner_type->SetSelection(1); // 1=MSCHAPv2
         break;
 
@@ -261,11 +260,11 @@ bool wxTTLSConfigWindow::TransferDataFromWindow()
         // This is not a provider-locked configuration. Save the data.
         switch (m_inner_type->GetSelection()) {
         case 0: // 0=PAP
-            m_cfg.m_inner.reset(new eap::config_method_pap(m_cfg_pap));
+            ((eap::config_method_ttls&)m_cfg).m_inner.reset(new eap::config_method_pap(m_cfg_pap));
             break;
 
         case 1: // 1=MSCHAPv2
-            m_cfg.m_inner.reset(new eap::config_method_mschapv2(m_cfg_mschapv2));
+            ((eap::config_method_ttls&)m_cfg).m_inner.reset(new eap::config_method_mschapv2(m_cfg_mschapv2));
             break;
 
         default: