diff --git a/README.md b/README.md
index 5a950a5edd..2649723d23 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 
 [![Build Status](https://travis-ci.org/nanoframework/nf-interpreter.svg?branch=master)](https://travis-ci.org/nanoframework/nf-interpreter)
-[![Join the chat at https://nanoframework.slack.com/](https://img.shields.io/badge/join%20us-on%20slack-orange.svg)](https://nanoframework.slack.com/)
+[![Join the chat at https://nanoframework.slack.com/](https://img.shields.io/badge/join%20us-on%20slack-orange.svg)](https://nanoframework.wordpress.com/slack-invite-form/)
 
 
 Welcome to the nanoFramework Interpreter repository!
diff --git a/src/CLR/Core/TypeSystem.cpp b/src/CLR/Core/TypeSystem.cpp
index 9dfb7cd748..06a4c8fb73 100644
--- a/src/CLR/Core/TypeSystem.cpp
+++ b/src/CLR/Core/TypeSystem.cpp
@@ -1535,7 +1535,7 @@ HRESULT CLR_RT_Assembly::CreateInstance( const CLR_RECORD_ASSEMBLY* header, CLR_
 
     NANOCLR_CLEAR(*skeleton);
 
-    if(header->GoodAssembly() == false) NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+    if(header->GoodAssembly() == false) NANOCLR_MSG_SET_AND_LEAVE(CLR_E_FAIL, L"Failed in type system: assembly is not good.\n");
 
     skeleton->m_header = header;
 
@@ -1795,7 +1795,7 @@ HRESULT CLR_RT_Assembly::Resolve_TypeRef()
 #if !defined(BUILD_RTM)
                 CLR_Debug::Printf( "Resolve: unknown scope: %08x\r\n", src->scope );
 #endif
-                NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+                NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: unknown scope: %08x\r\n", src->scope);
             }
 
             const char* szName = GetString( src->name );
@@ -1804,8 +1804,7 @@ HRESULT CLR_RT_Assembly::Resolve_TypeRef()
 #if !defined(BUILD_RTM)
                 CLR_Debug::Printf( "Resolve: unknown type: %s\r\n", szName );
 #endif
-
-                NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+				NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: unknown type: %s\r\n", szName);
             }
         }
         else
@@ -1813,7 +1812,7 @@ HRESULT CLR_RT_Assembly::Resolve_TypeRef()
             CLR_RT_Assembly* assm = m_pCrossReference_AssemblyRef[ src->scope ].m_target;
             if(assm == NULL)
             {
-                NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+				NANOCLR_MSG_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: assm is null\n");
             }
 
             const char* szNameSpace = GetString( src->nameSpace );
@@ -1824,7 +1823,7 @@ HRESULT CLR_RT_Assembly::Resolve_TypeRef()
                 CLR_Debug::Printf( "Resolve: unknown type: %s.%s\r\n", szNameSpace, szName );
 #endif
 
-                NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+				NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: unknown type: %s\r\n", szName);
             }
         }
     }
@@ -1849,7 +1848,7 @@ HRESULT CLR_RT_Assembly::Resolve_FieldRef()
             CLR_Debug::Printf( "Resolve Field: unknown scope: %08x\r\n", src->container );
 #endif
 
-            NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+			NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve Field: unknown scope: %08x\r\n", src->container);
         }
 
         const char* szName = GetString( src->name );
@@ -1860,7 +1859,7 @@ HRESULT CLR_RT_Assembly::Resolve_FieldRef()
             CLR_Debug::Printf( "Resolve: unknown field: %s\r\n", szName );
 #endif
 
-            NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+			NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: unknown field: %s\r\n", szName);
         }
     }
 
@@ -1884,7 +1883,7 @@ HRESULT CLR_RT_Assembly::Resolve_MethodRef()
             CLR_Debug::Printf( "Resolve Field: unknown scope: %08x\r\n", src->container );
 #endif
 
-            NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+			NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve Field: unknown scope: %08x\r\n", src->container);
         }
 
         const char* name = GetString( src->name );
@@ -1912,7 +1911,7 @@ HRESULT CLR_RT_Assembly::Resolve_MethodRef()
             CLR_Debug::Printf( "Resolve: unknown method: %s.%s.%s\r\n", qASSM->GetString( qTD->nameSpace ), qASSM->GetString( qTD->name ), name );
 #endif
 
-            NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+			NANOCLR_MSG1_SET_AND_LEAVE(CLR_E_FAIL, L"Resolve: unknown method: %s\r\n", name);
         }
     }
 
@@ -2845,7 +2844,7 @@ HRESULT CLR_RT_Assembly::PrepareForExecution()
         //Circular dependency
         _ASSERTE(false);
 
-        NANOCLR_SET_AND_LEAVE(CLR_E_FAIL);
+        NANOCLR_MSG_SET_AND_LEAVE(CLR_E_FAIL, L"Failed to prepare type system for execution\n");
     }
 
     if((m_flags & CLR_RT_Assembly::c_PreparedForExecution) == 0)
diff --git a/src/CLR/Include/nanoCLR_Interop.h b/src/CLR/Include/nanoCLR_Interop.h
index 095e4440f6..55f9b45a8b 100644
--- a/src/CLR/Include/nanoCLR_Interop.h
+++ b/src/CLR/Include/nanoCLR_Interop.h
@@ -35,16 +35,23 @@ __nfweak extern HRESULT NANOCLR_DEBUG_PROCESS_EXCEPTION( HRESULT hr, const char*
 #endif
 
 
-#define NANOCLR_HEADER()               HRESULT hr
-#define NANOCLR_CHECK_HRESULT(expr)    { if(FAILED(hr = (expr))) NANOCLR_LEAVE(); }
-#define NANOCLR_EXIT_ON_SUCCESS(expr)  { if(SUCCEEDED(hr = (expr))) NANOCLR_LEAVE(); }
-#define NANOCLR_SET_AND_LEAVE(expr)    { hr = (expr); NANOCLR_LEAVE(); }
-#define NANOCLR_CLEANUP()              hr = S_OK; nanoCLR_Cleanup:
-#define NANOCLR_CLEANUP_END()          NANOCLR_RETURN()
-#define NANOCLR_NOCLEANUP()            NANOCLR_CLEANUP(); NANOCLR_CLEANUP_END()
-#define NANOCLR_NOCLEANUP_NOLABEL()    hr = S_OK; NANOCLR_RETURN()
-#define FAULT_ON_NULL(ptr)             if(!(ptr)) NANOCLR_SET_AND_LEAVE(CLR_E_NULL_REFERENCE)
-#define FAULT_ON_NULL_ARG(ptr)         if(!(ptr)) NANOCLR_SET_AND_LEAVE(CLR_E_ARGUMENT_NULL)
+#define NANOCLR_HEADER()							HRESULT hr
+#define NANOCLR_CHECK_HRESULT(expr)					{ if(FAILED(hr = (expr))) NANOCLR_LEAVE(); }
+#define NANOCLR_EXIT_ON_SUCCESS(expr)				{ if(SUCCEEDED(hr = (expr))) NANOCLR_LEAVE(); }
+#define NANOCLR_SET_AND_LEAVE(expr)					{ hr = (expr); NANOCLR_LEAVE(); }
+#if defined(_MSC_VER)
+#define NANOCLR_MSG_SET_AND_LEAVE(expr, msg)		{ wprintf(msg); hr = (expr); NANOCLR_LEAVE(); }
+#define NANOCLR_MSG1_SET_AND_LEAVE(expr, msg, arg)	{ wprintf(msg, arg); hr = (expr); NANOCLR_LEAVE(); }
+#else
+#define NANOCLR_MSG_SET_AND_LEAVE(expr, msg)		{ hr = (expr); NANOCLR_LEAVE(); }
+#define NANOCLR_MSG1_SET_AND_LEAVE(expr, msg, arg)	{ hr = (expr); NANOCLR_LEAVE(); }
+#endif
+#define NANOCLR_CLEANUP()							hr = S_OK; nanoCLR_Cleanup:
+#define NANOCLR_CLEANUP_END()						NANOCLR_RETURN()
+#define NANOCLR_NOCLEANUP()							NANOCLR_CLEANUP(); NANOCLR_CLEANUP_END()
+#define NANOCLR_NOCLEANUP_NOLABEL()					hr = S_OK; NANOCLR_RETURN()
+#define FAULT_ON_NULL(ptr)							if(!(ptr)) NANOCLR_SET_AND_LEAVE(CLR_E_NULL_REFERENCE)
+#define FAULT_ON_NULL_ARG(ptr)						if(!(ptr)) NANOCLR_SET_AND_LEAVE(CLR_E_ARGUMENT_NULL)
 
 
 //    Correspondence between CLR C# and C++ native types: