diff --git a/src/CalcManager/pch.h b/src/CalcManager/pch.h
index a8155f9d..bba917d5 100644
--- a/src/CalcManager/pch.h
+++ b/src/CalcManager/pch.h
@@ -32,7 +32,6 @@
 
 #include <windows.h>
 #include <winerror.h>
-#include <ppltasks.h>
 
 #else