diff --git a/lib/core/convert.py b/lib/core/convert.py
index 5979c9d91..2cd58bb64 100644
--- a/lib/core/convert.py
+++ b/lib/core/convert.py
@@ -159,7 +159,7 @@ def stdoutencode(data):
         if IS_WIN:
             output = data.encode(sys.stdout.encoding, "replace")
 
-            if '?' in output:
+            if '?' in output and '?' not in data:
                 warnMsg = "cannot properly display Unicode characters "
                 warnMsg += "inside Windows OS command prompt "
                 warnMsg += "(http://bugs.python.org/issue1602). All "