Are you running a linux or solaris appserver? You may need to change the permissions of the tpassword.conf file.
Try changing the owner of the tpasswd.conf file from root to bladmin. Set permission on the file to 644
I fixed the issue by resetting the the BLAdmin and RBAC Admin passwords within the DB.
Here is my procedure:
1. Shutdown the application server
2. Remove the passwords from the database
3. Re-run the blappconf to recreate passwords.
4. Restart the application server.
Could you show the details for Steps 2 and 3 ?