The Self Service Portal is by default installed with 1 account having administrator access.
The login for this account are configured in the root web.config file (the superadminlogin and superadminpassword setting).
It is advised to not use this account and grant admin access to another users's account. The admin account should only be used for emergency situations and link this account to the Supervisor account. For more information on the Supervisor role please read User Access Control Section.