By default, with both ClearTrust 5.5.3 and Access Manager 6.x, the services are installed with "Log On As" Local System account
Some feel that the Local System account is too powerful account (full access to the system, including the directory service on domain controllers) and change it to Local User Account.
The same may be done with the Network Service account which is similar to an authenticated user account. The Network Service account has the same level of access to resources and objects as members of the Users group. This limited access helps safeguard your system if individual services or processes are compromised.
If you select an user account that does not have permission to log on as a service, the Services snap-in automatically grants that account the user rights that are required to log on as a service on the computer that you are managing. It is recommended that the user accounts that are used to log on as a service have the Password never expires check box selected in their properties dialog box and that they have strong passwords.