diff --git a/src/fileio.c b/src/fileio.c
index ae003a4..55397d7 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -13,6 +13,9 @@
 #include "forward.h"
 #include "fileio.h"
 #include "tidy.h"
+#if !defined(NDEBUG) && defined(_MSC_VER)
+#include "sprtf.h"
+#endif
 
 typedef struct _fp_input_source
 {
@@ -82,6 +85,9 @@ void TIDY_CALL TY_(filesink_putByte)( void* sinkData, byte bv )
 {
   FILE* fout = (FILE*) sinkData;
   fputc( bv, fout );
+#if !defined(NDEBUG) && defined(_MSC_VER)
+    SPRTF("%c",bv);
+#endif
 }
 
 void TY_(initFileSink)( TidyOutputSink* outp, FILE* fp )
diff --git a/src/localize.c b/src/localize.c
index 248c515..bcf0414 100755
--- a/src/localize.c
+++ b/src/localize.c
@@ -1164,15 +1164,21 @@ void tidy_out( TidyDocImpl* doc, ctmbstr msg, ... )
     {
         ctmbstr cp;
         enum { sizeBuf=2048 };
-        char *buf = TidyDocAlloc(doc,sizeBuf);
+        char *buf = (char *)TidyDocAlloc(doc,sizeBuf);
 
         va_list args;
         va_start( args, msg );
         TY_(tmbvsnprintf)(buf, sizeBuf, msg, args);
         va_end( args );
 
+#if !defined(NDEBUG) && defined(_MSC_VER)
+        add_std_out(0);
+#endif
         for ( cp=buf; *cp; ++cp )
           TY_(WriteChar)( *cp, doc->errout );
+#if !defined(NDEBUG) && defined(_MSC_VER)
+        add_std_out(1);
+#endif
         TidyDocFree(doc, buf);
     }
 }