ORA-16772: error switching over between primary and standby databases
Cause : There was an error during switchover of primary and standby databases.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Check the Data Guard broker log and Oracle alert log for more details.
Well, the reason for above error is that i have taken the above script from a 11g database and running it on 10g database. 11g has bring some changes in password management. Below code is executed on 11g and user created successfully, which is expected result.