diff --git a/gpt4all-backend/llmodel.cpp b/gpt4all-backend/llmodel.cpp
index 24b424c5..fdf3597a 100644
--- a/gpt4all-backend/llmodel.cpp
+++ b/gpt4all-backend/llmodel.cpp
@@ -11,6 +11,7 @@
 #include <cstdlib>
 #include <sstream>
 #ifdef _MSC_VER
+#include <windows.h>
 #include <processthreadsapi.h>
 #endif