TASK SCHEDULER SERVICE
Description: The Task Scheduler service enables you to perform automated tasks on a computer. With this service, you can schedule any program to run at any time or when a specific event occurs. The Task Scheduler monitors the time or event criteria that you choose and then executes the task when those criteria are met. The Task Scheduler service controls when tasks are activated, and hosts the tasks that are started by the service. By default, the Task Scheduler service is started when the operating system starts up. If this service is stopped or disabled, these tasks will not run at their scheduled times.
Scoping the Issue: First, determine the exact symptoms you are experiencing. Is the service failing to start? Does it start-up, and then stop? Each of these requires different troubleshooting steps to be carried out.
Note: The Task Scheduler service starts with the shared generic host processes for services, SVCHOST.EXE.
For Task Scheduler service start-up failures, check the Event logs for any Errors or Warnings. You should note any events with the Source of TaskScheduler. These may provide insight as to why the service is failing to start.
If the Task Scheduler service appears to start fine, but then stops a few seconds later, then we may be looking at a configuration problem or something crashing the shared svchost.exe process. At this point, you will want to isolate this shared process into its own process (see the AskPerf Blog link in the Additional Resources section below on how to do this), then get a dump of the .exe crashing/failing.
Data Gathering: In all instances, collecting either MPS Reports with the General, Internet and Networking, Business Networks and Server Components diagnostics, or a Performance-oriented MSDT manifest must be done. Additional required data may include:
- If the service fails to start, then grabbing a Process Monitor log while trying to start the Task Scheduler service would be beneficial.
- If the service starts, then stops soon after, or appears to be hung while processing a task, we may need to capture a dump (or a number of dumps) of the service while it is running. You can do this by running ADPLUS.VBS from the Windows Debugging Tools in crash mode or running Debug Diag to monitor the service. Please see our blog post, ‘Capturing Application Crash Dumps’ for more info.
Troubleshooting / Resolution: After you have gathered the data, there are some things to check – primarily for service failures:
- MPS Reports:
- Review the Event Logs for relevant events – specifically look for Event ID 26 (Application Popup), Event ID 1000 (Application Error) and Event ID 7034 (Service Control Manager) messages that correspond to the times that you are seeing unexpected service failures
- You should also check the Event Logs and Windows Update logs to see if there were any application updates or patches that preceded the unexpected behavior – there may be a correlation
- Dump File Analysis: If you are experienced at looking at dump files, there are some things that you can look for
- For hang dumps, check for application locks (for example, anti-virus locks), long-running threads and whether or not the application is waiting for data – for example from a network resource or a user input
- For crash dumps, running the command !analyze -v may provide a hint as to the cause of the failure. However, the output of this command may not always identify the real culprit
- Microsoft Technet: Task Scheduler Service
- AskPerf Blog: Getting Started with SVCHOST.EXE Troubleshooting
- AskPerf Blog: Task Scheduler Changes in Windows Vista and Windows Server 2008 – Part One
- AskPerf Blog: Task Scheduler Changes in Windows Vista and Windows Server 2008 – Part Two
- AskPerf Blog: Task Scheduler Changes in Windows Vista and Windows Server 2008 – Part Three