diff --git a/reactos/include/reactos/idl/svcctl.idl b/reactos/include/reactos/idl/svcctl.idl
index 2f737a5a489..8e92a50081b 100644
--- a/reactos/include/reactos/idl/svcctl.idl
+++ b/reactos/include/reactos/idl/svcctl.idl
@@ -18,11 +18,11 @@ const unsigned short SC_MAX_ARGUMENTS = 1024;
 typedef unsigned long SECURITY_INFORMATION;
 typedef [handle] LPSTR SVCCTL_HANDLEA;
 typedef [handle] LPWSTR SVCCTL_HANDLEW;
-typedef [context_handle] unsigned long SC_RPC_HANDLE;
+typedef [context_handle] ULONG_PTR SC_RPC_HANDLE;
 typedef SC_RPC_HANDLE* LPSC_RPC_HANDLE;
 typedef [context_handle] PVOID SC_RPC_LOCK;
 typedef SC_RPC_LOCK* LPSC_RPC_LOCK;
-typedef [context_handle] unsigned long SC_NOTIFY_RPC_HANDLE;
+typedef [context_handle] ULONG_PTR SC_NOTIFY_RPC_HANDLE;
 typedef SC_NOTIFY_RPC_HANDLE* LPSC_NOTIFY_RPC_HANDLE;
 typedef [range(0, 1024 * 4)] DWORD BOUNDED_DWORD_4K;
 typedef BOUNDED_DWORD_4K* LPBOUNDED_DWORD_4K;