diff --git a/reactos/include/ddk/ntifs.h b/reactos/include/ddk/ntifs.h
index 982bef28de4..45d0ba7d722 100644
--- a/reactos/include/ddk/ntifs.h
+++ b/reactos/include/ddk/ntifs.h
@@ -4890,12 +4890,12 @@ typedef struct _FS_FILTER_CALLBACK_DATA {
 } FS_FILTER_CALLBACK_DATA, *PFS_FILTER_CALLBACK_DATA;
 
 typedef NTSTATUS
-(NTAPI *PFS_FILTER_CALLBACK) (
+(*PFS_FILTER_CALLBACK) (
   _In_ PFS_FILTER_CALLBACK_DATA Data,
   _Out_ PVOID *CompletionContext);
 
 typedef VOID
-(NTAPI *PFS_FILTER_COMPLETION_CALLBACK) (
+(*PFS_FILTER_COMPLETION_CALLBACK) (
   _In_ PFS_FILTER_CALLBACK_DATA Data,
   _In_ NTSTATUS OperationStatus,
   _In_ PVOID CompletionContext);