Error ORA-16664 enabling Datagurd Configuration - ID Mismatch

Hi,

Recently I lost hours with this Issue, when trying to enable my Dataguard Configuration.

At Oracle Support -"Metalink" you will find some recommendations to solve this.
All recommendations leads to :
1- Set DG_BROKER_START=FALSE
2 - Delete the Dataguard Broker configuration  Files
3-Recreate Configuration

That's what I did consistently, and I got several errors such  as :

1. Error  ORA-16664
2. Error  ORA-16603
3. Error  ORA-12520

What's was missing in that recommendation is that we need to recreate the Standby.

In Prod Site 

1 - Set DG_BROKER_START=FALSE in Prod

2 - Remove Dataguard Configuration Files 

In STBY Site

3 - Stop and Delete all Standby datafiles

4 - Remove Dataguard Configuration Files in Standby Site

5 - Recreate Standby 

And no more pb.

Hope this may help