diff --git a/win/vncviewer/CConn.cxx b/win/vncviewer/CConn.cxx
index f289d38..6a6561d 100644
--- a/win/vncviewer/CConn.cxx
+++ b/win/vncviewer/CConn.cxx
@@ -16,6 +16,10 @@
  * USA.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <winsock2.h>
 #include <vncviewer/UserPasswdDialog.h>
 #include <vncviewer/CConn.h>
@@ -25,6 +29,9 @@
 #include <rfb/Security.h>
 #include <rfb/CMsgWriter.h>
 #include <rfb/Configuration.h>
+#ifdef HAVE_GNUTLS
+#include <rfb/CSecurityTLS.h>
+#endif
 #include <rfb/LogWriter.h>
 #include <rfb_win32/AboutDialog.h>
 
@@ -97,6 +104,9 @@
   applyOptions(options);
 
   CSecurity::upg = this;
+#ifdef HAVE_GNUTLS
+  CSecurityTLS::msg = this;
+#endif
 
   // Start the RFB protocol
   sock = s;
@@ -473,6 +483,34 @@
   sock->shutdown();
 }
 
+bool CConn::showMsgBox(int flags, const char* title, const char* text)
+{
+  UINT winflags = 0;
+  int ret;
+
+  /* Translate flags */
+  if ((flags & M_OK) != 0)
+    winflags |= MB_OK;
+  if ((flags & M_OKCANCEL) != 0)
+    winflags |= MB_OKCANCEL;
+  if ((flags & M_YESNO) != 0)
+    winflags |= MB_YESNO;
+  if ((flags & M_ICONERROR) != 0)
+    winflags |= MB_ICONERROR;
+  if ((flags & M_ICONQUESTION) != 0)
+    winflags |= MB_ICONQUESTION;
+  if ((flags & M_ICONWARNING) != 0)
+    winflags |= MB_ICONWARNING;
+  if ((flags & M_ICONINFORMATION) != 0)
+    winflags |= MB_ICONINFORMATION;
+  if ((flags & M_DEFBUTTON1) != 0)
+    winflags |= MB_DEFBUTTON1;
+  if ((flags & M_DEFBUTTON2) != 0)
+    winflags |= MB_DEFBUTTON2;
+
+  ret = MessageBox(NULL, text, title, flags);
+  return (ret == IDOK || ret == IDYES) ? true : false;
+}
 
 void
 CConn::showOptionsDialog() {
diff --git a/win/vncviewer/CConn.h b/win/vncviewer/CConn.h
index 3771154..62b131e 100644
--- a/win/vncviewer/CConn.h
+++ b/win/vncviewer/CConn.h
@@ -26,6 +26,7 @@
 #include <network/Socket.h>
 #include <rfb/CConnection.h>
 #include <rfb/Cursor.h>
+#include <rfb/UserMsgBox.h>
 #include <rfb/UserPasswdGetter.h>
 #include <rfb_win32/Registry.h>
 #include <rfb_win32/Handle.h>
@@ -43,7 +44,8 @@
     class CConn : public CConnection,
                   UserPasswdGetter,
                   DesktopWindow::Callback,
-                  rdr::FdInStreamBlockCallback
+                  rdr::FdInStreamBlockCallback,
+                  UserMsgBox
     {
     public:
       CConn();
@@ -77,6 +79,9 @@
       // - Get the server's preferred format
       const PixelFormat& getServerDefaultPF() const { return serverDefaultPF; }
 
+      // - Display message box
+      virtual bool showMsgBox(int flags, const char* title, const char* text);
+
       // Global user-config registry key
       static RegKey userConfigKey;
 
diff --git a/win/vncviewer/OptionsDialog.cxx b/win/vncviewer/OptionsDialog.cxx
index b3d72f2..abdd921 100644
--- a/win/vncviewer/OptionsDialog.cxx
+++ b/win/vncviewer/OptionsDialog.cxx
@@ -354,6 +354,8 @@
   OptionsInfo* dlg;
 };
 
+#ifdef HAVE_GNUTLS
+/* XXX: This class contains bunch of similar code to unix/vncviewer/CConn.cxx */
 class SecurityPage : public PropSheetPage {
 public:
   SecurityPage(OptionsInfo* dlg_, Security *security_)
@@ -369,18 +371,18 @@
 
     for (i = secTypes.begin(); i != secTypes.end(); i++) {
       switch (*i) {
-        case secTypeVeNCrypt:
-          enableVeNCryptFeatures(true);
-	  setItemChecked(IDC_VENCRYPT, true);
-          break;
-        case secTypeNone:
-          setItemChecked(IDC_ENC_NONE, true);
-          setItemChecked(IDC_AUTH_NONE, true);
-          break;
-        case secTypeVncAuth:
-          setItemChecked(IDC_ENC_NONE, true);
-          setItemChecked(IDC_AUTH_VNC, true);
-          break;
+      case secTypeVeNCrypt:
+        enableVeNCryptFeatures(true);
+        setItemChecked(IDC_VENCRYPT, true);
+        break;
+      case secTypeNone:
+        setItemChecked(IDC_ENC_NONE, true);
+        setItemChecked(IDC_AUTH_NONE, true);
+        break;
+      case secTypeVncAuth:
+        setItemChecked(IDC_ENC_NONE, true);
+        setItemChecked(IDC_AUTH_VNC, true);
+        break;
       }
     }
 
@@ -428,34 +430,126 @@
       }
     }
   }
+
   virtual bool onCommand(int id, int cmd) {
     switch (id) {
     case IDC_VENCRYPT:
-      enableVeNCryptFeatures(isItemChecked(IDC_VENCRYPT));
+      if (isItemChecked(IDC_VENCRYPT)) {
+        enableVeNCryptFeatures(true);
+        security->EnableSecType(secTypeVeNCrypt);
+      } else {
+        enableVeNCryptFeatures(false);
+        security->DisableSecType(secTypeVeNCrypt);
+      }
       break;
+
+    /* Process types without encryption */
     case IDC_ENC_NONE:
+      if (isItemChecked(IDC_ENC_NONE)) {
+      vlog.debug("here");
+        if (isItemChecked(IDC_AUTH_NONE))
+          security->EnableSecType(secTypeNone);
+        if (isItemChecked(IDC_AUTH_VNC))
+          security->EnableSecType(secTypeVncAuth);
+        if (isItemChecked(IDC_AUTH_PLAIN))
+          security->EnableSecType(secTypePlain);
+      } else {
+        security->DisableSecType(secTypeNone);
+        security->DisableSecType(secTypeVncAuth); 
+        security->DisableSecType(secTypePlain);
+      }
       break;
+
+    /* Process security types which use TLS encryption */
     case IDC_ENC_TLS:
+      if (isItemChecked(IDC_ENC_TLS)) {
+        if (isItemChecked(IDC_AUTH_NONE))
+          security->EnableSecType(secTypeTLSNone);
+        if (isItemChecked(IDC_AUTH_VNC))
+          security->EnableSecType(secTypeTLSVnc);
+        if (isItemChecked(IDC_AUTH_PLAIN))
+          security->EnableSecType(secTypeTLSPlain);
+      } else {
+        security->DisableSecType(secTypeTLSNone);
+        security->DisableSecType(secTypeTLSVnc);
+        security->DisableSecType(secTypeTLSPlain);
+      } 
       break;
+
+    /* Process security types which use X509 encryption */
     case IDC_ENC_X509:
       if (isItemChecked(IDC_ENC_X509)) {
         enableItem(IDC_LOAD_CACERT, true);
         enableItem(IDC_LOAD_CRLCERT, true);
+        if (isItemChecked(IDC_AUTH_NONE))
+          security->EnableSecType(secTypeX509None);
+        if (isItemChecked(IDC_AUTH_VNC))
+          security->EnableSecType(secTypeX509Vnc);
+        if (isItemChecked(IDC_AUTH_PLAIN))
+          security->EnableSecType(secTypeX509Plain);
       } else {
         enableItem(IDC_LOAD_CACERT, false);
         enableItem(IDC_LOAD_CRLCERT, false);
+        security->DisableSecType(secTypeX509None);
+        security->DisableSecType(secTypeX509Vnc);
+        security->DisableSecType(secTypeX509Plain);
       }
       break;
+
     case IDC_LOAD_CACERT:
       break;
+
     case IDC_LOAD_CRLCERT:
       break;
+
+    /* Process *None security types */
     case IDC_AUTH_NONE:
+      if (isItemChecked(IDC_AUTH_NONE)) {
+        if (isItemChecked(IDC_ENC_NONE))
+          security->EnableSecType(secTypeNone);
+        if (isItemChecked(IDC_ENC_TLS))
+          security->EnableSecType(secTypeTLSNone);
+        if (isItemChecked(IDC_ENC_X509))
+          security->EnableSecType(secTypeX509None);
+      } else {
+        security->DisableSecType(secTypeNone);
+        security->DisableSecType(secTypeTLSNone);
+        security->DisableSecType(secTypeX509None);
+      }
       break;
+
+    /* Process *Vnc security types */
     case IDC_AUTH_VNC:
+      if (isItemChecked(IDC_AUTH_VNC)) {
+        if (isItemChecked(IDC_ENC_NONE))
+          security->EnableSecType(secTypeVncAuth);
+        if (isItemChecked(IDC_ENC_TLS))
+          security->EnableSecType(secTypeTLSVnc);
+        if (isItemChecked(IDC_ENC_X509))
+          security->EnableSecType(secTypeX509Vnc);
+      } else {
+        security->DisableSecType(secTypeVncAuth);
+        security->DisableSecType(secTypeTLSVnc);
+        security->DisableSecType(secTypeX509Vnc);
+      }
       break;
+
+    /* Process *Plain security types */
     case IDC_AUTH_PLAIN:
+      if (isItemChecked(IDC_AUTH_PLAIN)) {
+        if (isItemChecked(IDC_ENC_NONE))
+          security->EnableSecType(secTypePlain);
+        if (isItemChecked(IDC_ENC_TLS))
+          security->EnableSecType(secTypeTLSPlain);
+        if (isItemChecked(IDC_ENC_X509))
+          security->EnableSecType(secTypeX509Plain);
+      } else {
+        security->DisableSecType(secTypePlain);
+        security->DisableSecType(secTypeTLSPlain);
+        security->DisableSecType(secTypeX509Plain);
+      }
       break;
+
     default:
       throw rdr::Exception("Unhandled action in SecurityPage");
     }
@@ -485,7 +579,7 @@
     setItemChecked(id, false);
   }
 };
-
+#endif
 
 OptionsDialog::OptionsDialog() : visible(false) {
 }
@@ -506,7 +600,9 @@
   InputsPage inputsPage(&info); pages.push_back(&inputsPage);
   MiscPage miscPage(&info); pages.push_back(&miscPage);
   DefaultsPage defPage(&info); if (view) pages.push_back(&defPage);
+#ifdef HAVE_GNUTLS
   SecurityPage secPage(&info, view->security); pages.push_back(&secPage);
+#endif
 
   // Show the property sheet
   ViewerOptions dialog(info, pages);