How to change task triggers using powershell? - powershell

Question

The script below removes the task triggers for each task ONLY if the tasks are in a folder. However my tasks are in the MAIN WINDOW in task scheduler. When you click on Task Scheduler Library, they are right there. They are not in any folder. However the $folder = $service.GetFolder('\') does not work. I tried it without the backlash and without the quotes, still does not work. What is going on ?
$service = New-Object -ComObject Schedule.Service
$service.Connect($env:COMPUTERNAME)
$folder = $service.GetFolder('\')
$tasks = $folder.gettasks(0)
foreach ($t in $tasks)
{
$definition = $t.Definition
$triggersCount = $definition.Triggers.Count
for($id=$triggersCount; $id -gt 0; $id--){
$definition.Triggers.Remove($id)
}
$folder.RegisterTaskDefinition($t.Name, $definition, 4, $null, $null, $null)
}

Answer 1

Get-ScheduledTask -TaskPath "\" may show all the tasks but there are no obvious commands or methods in the module to remove the triggers. I couldn't see a way and this answer seems to confirm it.
It's unclear from your question if $folder = $service.GetFolder('\') itself is producing an error, or if its the subsequent call to $tasks = $folder.gettasks(0). In this answer I'm assuming it's the latter, only because that's where I seem to have run into problems in my own environment.
I think this might be a combination of permissions and/or the hidden status of a task. Firstly, can you try running as elevated?
Reason I think this is after $folder = $service.GetFolder('\') I was able to get a list of tasks in the root folder, however only 2 of 9 were listed. When I ran in elevated I got 6 of 9.
I even tried the old PowerShell pack "TaskScheduler" module, which internally uses pretty much the same COM code, and I got the same results.
Now I was finally able to get the COM approach to show all 9 in the elevated session by flipping the GetTasks argument to 1:
$tasks = $folder.gettasks(1)
I believe the argument means to show or not to show hidden tasks, however it only accepts an [Int]. So, 0 = false, 1 = true. I confirmed this by looking at the code in the old "TaskScheduler" module. Putting a Boolean like $true in the argument doesn't work, only an [Int] will do.
Note: There is a hidden check box in the lower left, on the first tab
of the Task properties dialog. In may case the correlation matched what I ultimately found in the console.
At any rate give these 2 things a try:
Run as elevated.
Flip the argument to 1
Let me know how it turns out. Thanks.