diff --git a/sdk/include/psdk/ntdll.h b/sdk/include/psdk/ntdll.h
deleted file mode 100644
index b26a459e29e..00000000000
--- a/sdk/include/psdk/ntdll.h
+++ /dev/null
@@ -1,12 +0,0 @@
-#ifndef _NTDLL_H
-#define _NTDLL_H
-
-typedef enum _SHUTDOWN_ACTION {
-     ShutdownNoReboot,
-     ShutdownReboot,
-     ShutdownPowerOff
- } SHUTDOWN_ACTION;
-
-DWORD WINAPI NtShutdownSystem (SHUTDOWN_ACTION Action);
-
-#endif /* _NTDLL_H */