Will Windows Scheduled Tasks execute if the computer was off at the scheduled time?

If I schedule a task using windows task scheduler for, say, 2 minutes from now, and for some reason the computer is shut down 1 minute from now, and turned on 3 minutes from now, will the task that was scheduled still run?

If not, what can I do to mimic this functionality?

I'm writing a Java application that needs to execute a variety of system commands and I'd prefer the operating system actually manage the task execution phase. All I really need to have happen is for the task to execute as soon as possible by the operating system.

Mark Elliot

Posted 2011-07-20T00:08:19.693

Reputation: 370

Answers

No, it won't execute. The Task Scheduler in Vista and 7 can be configured to run missed instances, but XP's cannot. See the checkbox below called Run task as soon as possible after a scheduled start is missed.

However, all three can be set to wake the computer if it's asleep or hibernating.

enter image description here

afrazier

Posted 2011-07-20T00:08:19.693

Reputation: 21 316

1@RobertB, I just got here from the same search and your comment was very useful, thanks! – user2721465 – 2014-10-24T17:32:22.937

1+1 You beat me to it, but I am going to add a screenshot. – KCotreau – 2011-07-20T00:19:28.707

1I'm using schtasks to set up the task (programmatically), do you know the flag for "Run task as soon as possible"? – Mark Elliot – 2011-07-20T00:21:00.047

8Just got here from a search on "windows 7 task scheduler missed task". Figured I should add a tidbit I found out in my search: the "Run task as soon as possible after scheduled start is missed" doesn't run the missed task immediately. There's a 10-minute delay. So if it was scheduled at midnight and the PC was off, it won't run until 10 minutes after you turn it back on. (Zombie comment, but might be useful.) – RobertB – 2014-04-06T23:31:56.853

Im on Windows 10. Under the properties for the task...click the Conditions tab.

Under Power...check Wake the Computer to run this task.

Chris Catignani

Posted 2011-07-20T00:08:19.693

Reputation: 121

As it was said, you can't do this in XP but can in Vista+. Some programs (like Acronis True Image) use their own schedulers to overcome the system one's limitations.

To emulate this in XP, you can write a program (googling didn't readily reveal any publicly available existing ones) scheduled to run at system startup that would

check the system log for the last shutdown and startup times (or rather, Scheduler service's shutdown and startup times)
check task schedules against that
run the ones who have a start moment that falls into the interval

Caveats:

unless you can somehow call the corresponding Scheduler's functionality, you'll have to parse the schedules manually to calculate the next planned start time from a specific moment in the past
there's no "run as soon as possible" flag for tasks in XP, you'll have to invent a replacement (or grab everything indiscriminately)
since your task runs at system startup, some tasks may fail if they require facilities that have not been initialized yet

ivan_pozdeev

Posted 2011-07-20T00:08:19.693

Reputation: 1 468