When starting a secure enterprise server region or instance, the system authenticates the credentials of a specific user ID when doing so. This user ID is known as the default ESMAC user, and has a setting of mfuser. You may change this user ID by setting the environment variable ES_USR_DFLT_ESMAC in the Directory Server (MFDS) in the [ES-Environment] tag in Configuration Information.
If you change the credentials of the default ESMAC user ID, then you must ensure that it has the correct privileges to start a region. Failure to set these privileges means that you will be unable to start a region. See Make the User an MSS System Administrator for more details.