diff --git a/reactos/include/psdk/winbase.h b/reactos/include/psdk/winbase.h
index 0315d8638ba..2b819b01655 100644
--- a/reactos/include/psdk/winbase.h
+++ b/reactos/include/psdk/winbase.h
@@ -1050,6 +1050,7 @@ typedef struct _ACTIVATION_CONTEXT_BASIC_INFORMATION {
 	HANDLE hActCtx;
 	DWORD  dwFlags;
 } ACTIVATION_CONTEXT_BASIC_INFORMATION, *PACTIVATION_CONTEXT_BASIC_INFORMATION;
+typedef const struct _ACTIVATION_CONTEXT_BASIC_INFORMATION *PCACTIVATION_CONTEXT_BASIC_INFORMATION;
 typedef enum {
 	LowMemoryResourceNotification ,
 	HighMemoryResourceNotification