Account options

You can choose which account the service runs under. By default, most services run under the special LocalSystem account. You can set the service to log on under another account by opening the Account tab on the Service Properties window, and typing the account information.

If you choose to run the service under an account other than LocalSystem, that account must have the Log On As A Service privilege. This privilege can be granted from the Windows User Manager application under Advanced Privileges. The Service utility (dbsvc) can also be used to grant this privilege.

When an icon appears in the system tray

If a service runs under LocalSystem, and Allow Service To Interact With Desktop is selected on the Service Properties window, an icon appears on the desktop of every user logged in to Windows on the computer running the service. Any user can open the application window and stop the program running as a service.
If a service runs under LocalSystem, and Allow Service To Interact With Desktop is cleared on the Service Properties window, no icon appears on the desktop for any user. Only users with permissions to change the state of services can stop the service.
If a service runs under another account, no icon appears on the desktop. Only users with permissions to change the state of services can stop the service.

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