diff --git a/dlls/advapi32/registry.c b/dlls/advapi32/registry.c
index 2d8e1bbcd8f..e32f48a5b7e 100644
--- a/dlls/advapi32/registry.c
+++ b/dlls/advapi32/registry.c
@@ -212,6 +212,8 @@ static NTSTATUS open_key( HKEY *retkey, DWORD options, ACCESS_MASK access, OBJEC
     DWORD pos = 0, i = 0, len = attr->ObjectName->Length / sizeof(WCHAR);
     UNICODE_STRING str;
 
+    *retkey = NULL;
+
     if (!force_wow32)
     {
         if (options & REG_OPTION_OPEN_LINK) attr->Attributes |= OBJ_OPENLINK;