diff --git a/src/escape_string.cpp b/src/escape_string.cpp
index 766afba6b..aa6fcaa5e 100644
--- a/src/escape_string.cpp
+++ b/src/escape_string.cpp
@@ -603,7 +603,7 @@ namespace libtorrent
 		ws.resize(s.size() + 1);
 		std::size_t size = MultiByteToWideChar(CP_ACP, 0, s.c_str(), -1, &ws[0], ws.size());
 		if (size == std::size_t(-1)) return s;
-		if (size != 0 && ret[size - 1] == '\0') --size;
+		if (size != 0 && ws[size - 1] == '\0') --size;
 		ws.resize(size);
 		std::string ret;
 		libtorrent::wchar_utf8(ws, ret);