If you are receiving an error that reads, an error has occurred, contact your admin, and if you’ve already contacted yourself,
then this is occurring when you’ve clicked Generate a key from Application Management > manage service applications > Secure Store Service Application > manage
Make sure that the account that the secure store service application is using- (Security > configure service applications) has db_owner on the secure store database in SQL and try again.
To check the db_owner login role:
1. Login to the SQL database server with an account that can access the SQL database
2. Expand the Security node and right click on the account that is running the service, per the configure service applications page from your central admin
3. Select User mapping, scroll down to the SecureStoreServiceApplication Database and make this account db_owner, if it isn’t.