Windows Task Scheduler "Launch request ignored, instance already running"
I have a task which triggers every 5 min every day. But recently, I found the task always failed between only 8:00 am to 9:00 am but all the other tasks (some trigger every 1 min) do not have any problem. So I have no idea what's wrong.
From log below, I can see there was a trigger at 8:20 and it finally terminated at 8:30. Actually, the task is quite simple to take less than 1 min to finish. So I have no idea why there are "Launch request ignored, instance already running" warnings.
Answer
It can happen that a task that runs as scheduled task simply does not terminate. Whether this is a fault of task manager or the script is unknown, but both can be at fault here. For example, if the batch file contains a pause statement, the batch file expects a keypress to continue. The task scheduler will never send it, and this the script never finishes.
Try changing few options in task scheduler. At the bottom of the property window, you will find:
'If the task is already running, the following applies" make it "Do start a
new intstance".
Change this to "Run a new instance in parallel"
This should solve your problem.