1. Shutdown the DB
2. Stop all services on Windows related to oracle
3. Stop the Distributed Co-ordinator service on windows.
4. Backup the DB and the inventory.
5. Patch the Oracle Software ...
6. Start the DB in upgrade mode ... startup upgrade
7. Execute catupgrd.sql for patching the DB.
8. shutdown immediate and startup the DB
9. Finally check the dba_registry