Windows Task Scheduler
Other names | taskschd.msc |
---|---|
Developer(s) | Microsoft |
Initial release | 1995 |
Written in | C++ |
Included with |
|
Predecessor | System Agent |
Service name | Task Scheduler (Schedule ) |
Type | Windows service |
Website | docs |
Task Scheduler (formerly Scheduled Tasks)
Task Scheduler can be compared to
Versions
Task Scheduler 1.0
Task Scheduler 1.0 is included with
mstask.exe
. It also displays a status icon in the notification area on Windows 95 and Windows 98 and runs as a hidden service on Windows Me, but can be made to show a tray icon.[1] Computer programs and scripts can access the service through six COM interfaces.[10] Microsoft provides a scheduling agent DLL, a sample VBScript and a configuration file to automate Task Scheduler.[11]In addition to the graphical user interface for Task Scheduler in Control Panel, Windows provides two command-line tools for managing scheduled task: at.exe
(deprecated)[12] and schtasks.exe
.[5][13][14] However, at.exe
cannot access tasks created or modified by Control Panel or schtasks.exe
.[15] Also, tasks created with at.exe
are not interactive by default; interactivity needs to be explicitly requested. The binary ".job" files which the AT command produces are stored in the %WINDIR%\Tasks directory.[16][17]
Task Scheduler 2.0
Task Scheduler 2.0 was introduced with
Task Scheduler 2.0 exposes an API to allow computer programs and scripts create tasks.[19][23] It consists of 42 COM interfaces.[24] The Windows API does not, however, include a managed wrapper for Task Scheduler though an open source implementation exists.[25] The job files for Task Scheduler 2.0 are XML-based, and are human-readable, conforming to the Task Scheduler Schema.[19][23]
Other features
- New security features, including using Credential Manager to passwords for tasks on workgroup computers and using Active Directory for task credentials on domain-joined computers so that they cannot be retrieved easily. Also, scheduled tasks are executed in their own session, instead of the same session as system services or the current user.
- Ability to wake up a machine remotely or using BIOS timer from sleep or hibernation to execute a scheduled task or run a previously scheduled task after a machine gets turned on.
- Ability to attach tasks to events directly from the Event Viewer.
Tasks
The Task Scheduler service works by managing Tasks; Task refers to the action (or actions) taken in response to trigger(s). A task is defined by associating a set of actions, which can include launching an application or taking some custom-defined action, to a set of triggers, which can either be time-based or event-based. In addition, a task also can contain metadata that defines how the actions will be executed, such as the security context the task will run in. Tasks are serialized to .job
files and are stored in the
ITaskFolder
interface or the TaskFolder
scripting object and individual tasks using the IRegisteredTask
interface or RegisteredTask
object.[26]Column 'Last Result'
The Last Result column displays a completion code. The common codes for scheduled tasks are:[27][28]
- 0 or 0x0: The operation completed successfully.
- 1 or 0x1: Incorrect function called or unknown function called.
- 2 or 0x2: File not found.
- 10 or 0xa: The environment is incorrect.
- 0x00041300: Task is ready to run at its next scheduled time.
- 0x00041301: The task is currently running.
- 0x00041302: The task has been disabled.
- 0x00041303: The task has not yet run.
- 0x00041304: There are no more runs scheduled for this task.
- 0x00041305: One or more of the properties that are needed to run this task have not been set.
- 0x00041306: The last run of the task was terminated by the user.
- 0x00041307: Either the task has no triggers or the existing triggers are disabled or not set.
- 0x00041308: Event triggers do not have set run times.
- 0x80010002: Call was canceled by the message filter
- 0x80041309: A task's trigger is not found.
- 0x8004130A: One or more of the properties required to run this task have not been set.
- 0x8004130B: There is no running instance of the task.
- 0x8004130C: The Task Scheduler service is not installed on this computer.
- 0x8004130D: The task object could not be opened.
- 0x8004130E: The object is either an invalid task object or is not a task object.
- 0x8004130F: No account information could be found in the Task Scheduler security database for the task indicated.
- 0x80041310: Unable to establish existence of the account specified.
- 0x80041311: Corruption was detected in the Task Scheduler security database
- 0x80041312: Task Scheduler security services are available only on Windows NT.
- 0x80041313: The task object version is either unsupported or invalid.
- 0x80041314: The task has been configured with an unsupported combination of account settings and run time options.
- 0x80041315: The Task Scheduler Service is not running.
- 0x80041316: The task XML contains an unexpected node.
- 0x80041317: The task XML contains an element or attribute from an unexpected namespace.
- 0x80041318: The task XML contains a value which is incorrectly formatted or out of range.
- 0x80041319: The task XML is missing a required element or attribute.
- 0x8004131A: The task XML is malformed.
- 0x0004131B: The task is registered, but not all specified triggers will start the task.
- 0x0004131C: The task is registered, but may fail to start. Batch logon privilege needs to be enabled for the task principal.
- 0x8004131D: The task XML contains too many nodes of the same type.
- 0x8004131E: The task cannot be started after the trigger end boundary.
- 0x8004131F: An instance of this task is already running.
- 0x80041320: The task will not run because the user is not logged on.
- 0x80041321: The task image is corrupt or has been tampered with.
- 0x80041322: The Task Scheduler service is not available.
- 0x80041323: The Task Scheduler service is too busy to handle your request. Please try again later.
- 0x80041324: The Task Scheduler service attempted to run the task, but the task did not run due to one of the constraints in the task definition.
- 0x00041325: The Task Scheduler service has asked the task to run.
- 0x80041326: The task is disabled.
- 0x80041327: The task has properties that are not compatible with earlier versions of Windows.
- 0x80041328: The task settings do not allow the task to start on demand.
- 0x80070002: The Task Scheduler cannot find the file.
- 0x800710E0: The operator or administrator has refused the request.
- 0xC000013A: The application terminated as a result of a CTRL+C.
- 0xC0000142: The application failed to initialize properly.
Bugs
On Windows 2000 and Windows XP, when a computer is prepared for
On Windows Vista or Windows Server 2008, the next execution time displayed in Task Scheduler may be wrong. Microsoft issued a hotfix to remedy this issue.[30]
See also
- cron, job scheduler for Unix-like operating systems
References
- ^ a b "How to Enable the Scheduled Tasks Icon in Windows Me". Support. Microsoft. January 29, 2007. Archived from the original on January 30, 2008.
- ^ "Keep your Windows desktop in shape with Task Scheduler". TechRepublic. January 4, 2002.
- ^ "What is Task Scheduler?". Computer Hope. November 30, 2020.
- ^ Al Fasoltd (March 29, 1998). "Windows 98: Stable and fast, as well as 'new and improved'". The Syracuse Newspapers. Retrieved October 6, 2007.
- ^ ISBN 978-0470930908.
- ISBN 978-0134049359.
- ^ ISBN 978-0672319655.
- ISBN 978-0132715539.
- ^ MSDN. Microsoft. Retrieved October 6, 2007.
- MSDN. Microsoft. Retrieved May 30, 2014.
- ^ "Task Scheduler Using VBScript". Download Center. Microsoft. March 22, 2004. Archived from the original on May 4, 2006.
- ^ "MS-DOS and Windows command line at command". Computer Hope. Retrieved March 7, 2021.
- ^ "Schtasks". Microsoft TechNet. Microsoft. Retrieved May 18, 2014.
- ^ "At". Microsoft TechNet. Microsoft. Retrieved May 18, 2014.
- ^ "How To Use the AT Command to Schedule Tasks". Support. Microsoft. October 30, 2006.
- ISBN 978-0080489872.
- ^ "Applications Started with AT Are Not Interactive". Support. Microsoft. February 20, 2007. Archived from the original on October 29, 2004.
- ISBN 978-0789737816.
- ^ ISBN 978-1118058695.
- PCWorld. Retrieved March 15, 2021.
- ^ "Windows Vista Task Scheduler". Microsoft TechNet. Microsoft. March 3, 2006. Archived from the original on April 12, 2006. Retrieved April 24, 2006.
- ^ "Description of the scheduled tasks in Windows Vista". August 24, 2007. Archived from the original on October 22, 2007.
- ^ MSDN. Microsoft. Archived from the originalon December 26, 2007. Retrieved October 6, 2007.
- MSDN. Microsoft. Retrieved May 30, 2014.
- ^ "C# API for Task Scheduler 2.0". Stack Overflow. Retrieved July 24, 2019.
- MSDN. Microsoft. Retrieved October 6, 2007.
- ^ "How to troubleshoot scheduled tasks in Windows XP and in Windows Server 2003". Support. Microsoft. May 22, 2013. Retrieved September 3, 2013.
- MSDN. Microsoft.
- ^ "Scheduled tasks may not start if you used a System Preparation image to install Windows XP or Windows 2000". Support. Microsoft. July 1, 2004. Archived from the original on September 26, 2008. Retrieved May 19, 2012.
- ^ "The value in the Next Run Time field in Task Scheduler is incorrect in Windows Vista and in Windows Server 2008". Support. Microsoft. October 15, 2008. Archived from the original on December 11, 2008.
Further reading
- Leonhard, Woody; Rusen, Ciprian (2021). Windows 10 All-in-One For Dummies. ISBN 978-1119680574.
- Knittel, Brian; McFedries, Paul (2014). Windows 8.1 in Depth. ISBN 978-0789752819.
- Bott, Ed; Siechert, Carl; Stinson, Craig (2009). Windows 7 Inside Out. ISBN 978-0735636842.
- Ruest, Danielle; Ruest, Nelson (2008). Microsoft Windows Server 2008: The Complete Reference. ISBN 978-0071596466.
- Cowart, Robert; Knittel, Brian (2008). Special Edition Using Microsoft Windows Vista. ISBN 978-0789737816.
External links
- Task Scheduler on MSDN
- The Log File in the Task Scheduler May Be Incorrectly Formatted and Difficult to Read - Archived October 16, 2007, at the Wayback Machine
- Unable to Delete Text in the Task Scheduler Log File
- Task Scheduler Service Does Not Start
- Scheduled Program Does Not Start in Task Scheduler - Archived August 21, 2006, at the Wayback Machine
- Cannot Disable Task Scheduler