diff --git a/src/slic3r/Utils/FixModelByWin10.hpp b/src/slic3r/Utils/FixModelByWin10.hpp
index 4f0acd90a..a1ef4511b 100644
--- a/src/slic3r/Utils/FixModelByWin10.hpp
+++ b/src/slic3r/Utils/FixModelByWin10.hpp
@@ -3,6 +3,8 @@
 
 #include <string>
 
+class wxProgressDialog;
+
 namespace Slic3r {
 
 class Model;