diff --git a/reactos/ntoskrnl/include/internal/cm.h b/reactos/ntoskrnl/include/internal/cm.h
index 62f4010f20b..52637b29bc9 100644
--- a/reactos/ntoskrnl/include/internal/cm.h
+++ b/reactos/ntoskrnl/include/internal/cm.h
@@ -1607,6 +1607,7 @@ extern BOOLEAN CmpProfileLoaded;
 extern PCMHIVE CmiVolatileHive;
 extern LIST_ENTRY CmiKeyObjectListHead;
 extern BOOLEAN CmpHoldLazyFlush;
+extern UNICODE_STRING CmRegistryMachineSystemName;
 
 //
 // Inlined functions