Scheduled task last result 0xff

Scheduled tasks are contained in C:\Windows\System32\Tasks\ and contain XML files. While the Petri article is a good solution for Windows 8 and Windows Server 2012, that's not a complete solution. This should allow you to find the tasks with a specific command or argument, and replace those.

$computer = "localhost"

$oldCommand = "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"
$oldArguments = "-File `"C:\Users\Public\Scripts\oldScript.ps1`""
$newCommand = "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"
$newArguments = "-File `"C:\Users\Public\Scripts\newScript.ps1`""

$tasks = Get-ChildItem "\\$computer\c$\Windows\System32\Tasks\" | Where-Object {
    $_.PSIsContainer -eq $false `
    -and `
    (([xml](Get-Content -Path $_.FullName)).Task.Actions.Exec.Command -like $oldCommand) `
    -and `
    (([xml](Get-Content -Path $_.FullName)).Task.Actions.Exec.Arguments -like $oldArguments)
    }

$tasks | ForEach-Object {
    $xml = [xml](Get-Content -Path $_.FullName)
    $xml.Task.Actions.Exec.Command = $newCommand
    $xml.Task.Actions.Exec.Arguments = $newArguments
    $xml.Save($_.FullName)
    }

I resolved the issue by calling the batchfile under "Program/Script" & set the complete absolute path in "Start In (optional):" box like below:

Program/Script: Process.cmd
Start In (optional): T:\Processing\clients\myTest

Hope this helps.