1 files changed, 1 insertions, 0 deletions

diff --git a/mtp/btree.hpp b/mtp/btree.hpp
index b284e4f4b..e1aad3636 100755
--- a/mtp/btree.hpp
+++ b/mtp/btree.hpp
@@ -18,6 +18,7 @@
 #define BTREE_HPP
 
 #include <vector>
+#include <string>
 #include <map>
 #include "MtpTypes.h"