diff --git a/src/file_win.cpp b/src/file_win.cpp
index a63680a44..eb6814a34 100644
--- a/src/file_win.cpp
+++ b/src/file_win.cpp
@@ -64,7 +64,7 @@ namespace
 		std::string ret;
 		ret.resize(size);
 		size = wcstombs(&ret[0], ws.c_str(), size + 1);
-		ret.resize(size);
+		ret.resize(size-1);
 		return ret;
 	}