Summary

Many programs do not behave properly when scheduled to run under the Local System account.

More Information

The Arcana Scheduler provides an option to run scheduled programs under the Local System account rather than a user account. As the user's guide says:

This option generally should not be used and is provided primarily for backwards compatibility with prior versions of the Scheduler. Programs run under the Local System account lack many things that a program run under a user account has, including access to printers, network resources, and a user profile. Many programs will not behave properly when run under the Local System account.

The Local System account is not the same as the "Local Administrator" account. It is not a user account at all. The Local System account is intended for use by the operating system, and by applications (such as services) that essentially act as a part of the operating system and are specifically designed to work when run under that account.

Most applications that you schedule are not designed to be run under the Local System account. If they were, they'd probably be running on their own, as services, not under the Scheduler.

The Local System account is by design limited in what it can do. Most significantly:

  • It has no user profile. Many applications expect to be able to load settings from and save settings to the user's profile when they run. They're not built to handle the possibility that there won't be a profile, so they fail. This is particularly true of VB applications.
  • Because it has no profile, it has no printers (because printers are defined in each user's profile). Applications run under this account won't be able to print.
  • It has none of the many other things that are associated with a user profile. Like a MAPI profile, so your application can't use MAPI to send e-mail.
  • It only has access to resources on the local system (hence the name). It does not have access to network resources.

Please do not use the Local System account when scheduling programs unless you understand the limitations of this account.