diff --git a/appveyor.yml b/appveyor.yml
index 70b93b137..473dbb013 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -23,7 +23,6 @@ environment:
   - variant: test_release
     compiler: msvc-14.0
     model: 64
-    python: 1
     linkflags: '"/LIBPATH:C:\\openssl-1.0.1p-vs2015\\lib64"'
     include: '"c:\\openssl-1.0.1p-vs2015\\include"'
   - variant: test_debug
diff --git a/bindings/python/src/error_code.cpp b/bindings/python/src/error_code.cpp
index caea76ba9..e23bbc511 100644
--- a/bindings/python/src/error_code.cpp
+++ b/bindings/python/src/error_code.cpp
@@ -34,6 +34,17 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/bdecode.hpp>
 #include <libtorrent/upnp.hpp>
 #include <libtorrent/socks5_stream.hpp>
+
+namespace boost
+{
+	// this fixe mysterious link error on msvc
+	boost::system::error_category const volatile*
+	get_pointer(boost::system::error_category const volatile* p)
+	{
+		return p;
+	}
+}
+
 #include "boost_python.hpp"
 
 using namespace boost::python;
@@ -42,7 +53,9 @@ using boost::system::error_category;
 
 void bind_error_code()
 {
-    class_<boost::system::error_category, boost::noncopyable>("error_category", no_init)
+    using boost::noncopyable;
+
+    class_<boost::system::error_category, noncopyable>("error_category", no_init)
         .def("name", &error_category::name)
         .def("message", &error_category::message)
         .def(self == self)
@@ -56,34 +69,34 @@ void bind_error_code()
         .def("value", &error_code::value)
         .def("clear", &error_code::clear)
         .def("category", &error_code::category
-           , return_internal_reference<>())
+           , return_value_policy<reference_existing_object>())
         .def("assign", &error_code::assign)
         ;
 
     def("get_libtorrent_category", &get_libtorrent_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
     def("get_upnp_category", &get_upnp_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
     def("get_http_category", &get_http_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
     def("get_socks_category", &get_socks_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
 #if TORRENT_USE_I2P
     def("get_i2p_category", &get_i2p_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 #endif
 
     def("get_bdecode_category", &get_bdecode_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
     def("generic_category", &boost::system::generic_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 
     def("system_category", &boost::system::system_category
-       , return_internal_reference<>());
+       , return_value_policy<reference_existing_object>());
 }
 
diff --git a/bindings/python/src/session.cpp b/bindings/python/src/session.cpp
index 686c99193..5a6063ffa 100644
--- a/bindings/python/src/session.cpp
+++ b/bindings/python/src/session.cpp
@@ -17,13 +17,23 @@
 #include <libtorrent/aux_/session_impl.hpp> // for settings_map()
 #include <libtorrent/torrent_info.hpp>
 #include <libtorrent/kademlia/item.hpp> // for sign_mutable_item
-
+#include <libtorrent/alert.hpp>
 #include <libtorrent/extensions/lt_trackers.hpp>
 #include <libtorrent/extensions/metadata_transfer.hpp>
 #include <libtorrent/extensions/smart_ban.hpp>
 #include <libtorrent/extensions/ut_metadata.hpp>
 #include <libtorrent/extensions/ut_pex.hpp>
 
+namespace boost
+{
+	// this fixes mysterious link error on msvc
+	libtorrent::alert const volatile*
+	get_pointer(libtorrent::alert const volatile* p)
+	{
+		return p;
+	}
+}
+
 #include "gil.hpp"
 #include "bytes.hpp"
 
@@ -323,8 +333,11 @@ namespace
     alert const*
     wait_for_alert(lt::session& s, int ms)
     {
-        allow_threading_guard guard;
-        alert const* a = s.wait_for_alert(milliseconds(ms));
+        alert const* a;
+        {
+            allow_threading_guard guard;
+            a = s.wait_for_alert(milliseconds(ms));
+        }
         return a;
     }
 
@@ -415,10 +428,9 @@ namespace
         }
 
         list ret;
-        for (std::vector<alert*>::iterator i = alerts.begin()
-            , end(alerts.end()); i != end; ++i)
+        for (alert* a : alerts)
         {
-            ret.append(boost::python::ptr(*i));
+            ret.append(boost::python::ptr(a));
         }
         return ret;
     }
@@ -759,8 +771,7 @@ void bind_session()
         .def("load_state", &load_state, (arg("entry"), arg("flags") = 0xffffffff))
         .def("save_state", &save_state, (arg("entry"), arg("flags") = 0xffffffff))
         .def("pop_alerts", &pop_alerts)
-        .def("wait_for_alert", &wait_for_alert, return_internal_reference<>()
-        )
+        .def("wait_for_alert", &wait_for_alert, return_internal_reference<>())
         .def("add_extension", &add_extension)
 #ifndef TORRENT_NO_DEPRECATE
 #if TORRENT_USE_I2P
diff --git a/simulation/Jamfile b/simulation/Jamfile
index c3036a051..5e44398ba 100644
--- a/simulation/Jamfile
+++ b/simulation/Jamfile
@@ -16,6 +16,7 @@ project
 	<source>setup_dht.cpp
 	<source>create_torrent.cpp
 	<source>utils.cpp
+	<toolset>msvc:<cflags>/wd4275
 	: default-build
 	<threading>multi
 	<invariant-checks>full
diff --git a/simulation/libsimulator b/simulation/libsimulator
index 0c796e3e0..1df1d6083 160000
--- a/simulation/libsimulator
+++ b/simulation/libsimulator
@@ -1 +1 @@
-Subproject commit 0c796e3e0dea7ca05eef3ded2cf3806ef19a1413
+Subproject commit 1df1d608358ed93cc5024ad731df7d047508554f