Using Task Scheduler

Task Scheduler is an MMC snap-in that lets you schedule automated tasks that perform actions according to scheduled times or when specific events occur. Task Scheduler maintains a library of all scheduled tasks and provides an organized view of these tasks and an interface for managing them. The Windows 7 version of Task Scheduler is essentially the same as that found in Windows Vista, which improved upon earlier versions of Windows by providing a better user interface, more flexible scheduling, enhanced security, and improved manageability. Specifically, the following enhancements to Task Scheduler were introduced in Windows Vista:

• User interface improvements The Windows Vista version of Task Scheduler introduced a completely new user interface based on the MMC. This interface includes a number of new conditions and filters to assist administrators in defining and managing scheduled tasks.
• Scheduling improvements Time-based task launch is improved, with more detailed control and enhanced scheduling options. One key improvement allows you to chain a series of actions together instead of having to create multiple scheduled tasks. You can schedule tasks on demand for execution when a specified event is logged to an event log. You can configure scheduled tasks to wake a computer from sleep or hibernation or to run only when the computer is idle. You can also run previously scheduled tasks when a powered-down computer is turned back on. Scalability has also been improved by removing limitations on the number of registered tasks and allowing multiple instances of a task to run in parallel or in sequence.
• Security improvements New security features include use of Credentials Manager (CredMan) to securely store passwords needed for running tasks, and also supporting Service for User (S4U) for many scenarios such that passwords do not need to be stored at all. Improved credentials management provided by S4U and Credentials Manager also increases reliability and reduces maintenance overhead. To further increase security, scheduled tasks are executed in their own session instead of the same session as system services or the current user:
  • Separate per-user credentials are required.
  • System tasks run in the system session (session 0), while user tasks run in the user's session.
• Administrative improvements The version of Task Scheduler in Windows Vista introduces features that enhance the administration experience for scheduled tasks. Scheduled tasks may be activated by Event Log events and may be synchronized using operational events fired by the service, which can be found under Applications And Services Logs/Microsoft/Windows/Task Scheduler/Operational log. Tasks may be configured to retry on failure and activated when resources become available, as in the case of mobile devices that may miss run times of scheduled tasks. Control and task status monitoring has been improved and now provides detailed failure reporting and task history. Status feedback has been significantly improved. For example, using the detailed events logged by the Task Scheduler about task operation, an administrator can set up an e-mail to be sent to her when a failure occurs, including a complete runtime history of the event. In addition, the complete history of executed scheduled tasks can be easily reviewed, and at any time the administrator can view the list of currently running tasks and run or stop tasks on demand. To assist administrators in scripting complex tasks, the Task Scheduler API is also fully available to scripting languages.
• Platform and manageability improvements The version of Task Scheduler in Windows Vista enables several new features that improve platform operations and manageability. Infrastructure features for application monitoring now allow hosting and activation of troubleshooters and other corrective actions. Periodic data collection has been implemented to improve event detection. Task process prioritization has been improved and quotas may be assigned. Computer resources are used more efficiently by activating tasks based on a true idle state, defined by a combination of the following criteria:
  • CPU, memory, and I/O usage
  • User presence
  • Nonpresentation mode