ORA-29386: plan or consumer group string is mandatory and cannot be deleted or modified
Cause : An attempt was made to delete or modify the specified mandatory plan or consumer group.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Do not attempt to delete or modify mandatory plans and consumer groups.
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.