Powershell unregister-ScheduledTask - powershell

Question

I'm trying to remove schedule task on remote servers.
Invoke-Command -ComputerName "name" {Unregister-ScheduledTask -TaskName $task -WhatIf}
I get the following error
Cannot validate argument on parameter 'TaskName'. The argument is null. Provide a valid value for the argument, and then try running the command again.
+ CategoryInfo : InvalidData: (:) [Unregister-ScheduledTask], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationError,Unregister-ScheduledTask
+ PSComputerName : name
$Task='task'
If I specify the "Taskname" in text and not variable it works.
Invoke-Command -ComputerName "name" {Unregister-ScheduledTask -TaskName "task" -WhatIf}
What if: Performing operation 'Delete' on Target '\task'.

Answer 1

To pass a named variable to a scriptblock, do:
Invoke-Command -ComputerName $Computer -ScriptBlock {param($task) Unregister-ScheduledTask -TaskName $task } -ArgumentList $TaskName
or use the $args Automatic variable like:
Invoke-Command -ComputerName $Computer -ScriptBlock { Unregister-ScheduledTask -TaskName $args[0] } -ArgumentList $TaskName

Answer 2

Create the unregister file like this one I use to clear unwanted scheduled tasks:
#TaskSchdOptimizer.ps1
get-scheduledtask | where {$_.taskname -like "Optimize Start Menu Cache Files*"} | Unregister-ScheduledTask -Confirm:$false
get-scheduledtask | where {$_.taskname -like "GoogleUpdateTaskMachine*"} | Unregister-ScheduledTask -Confirm:$false
get-scheduledtask | where {$_.taskname -like "User_Feed*"} | Unregister-ScheduledTask -Confirm:$false
and then copy the file to the servers, like I do my $profile:
#Copy-UnregisterFile.ps1
$serverListFile = gc .\yourinputfolder\serverlist.txt
$file_dir="driveletter$\whereyourfileis" #DO NOT put an ending "\"!!!
#$file_name="yourunregisterfile.ps1" #<-- put yours here and remove #
$from="$file_dir\$file_name"
$dest="driveletter$\folderwhereyouwanttorunitfrom" #DO NOT put an ending "\"!!!
Foreach ($Server in $ServerListFile){
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12 #<-- needed now since 2016
if ((test-path "\\$Server\driveletter$\folderwhereyouwanttorunitfrom") -ne $true){New-Item -ErrorAction Ignore -ItemType directory -Path "\\$server\driveletter$\folderwhereyouwanttorunitfrom" -Force -verbose}
Copy-Item -Path $from -Destination \\$Server\$dest\ -Force -Verbose
Write-Host " $server : copied $file_name to $dest"
}
...after that run your invoke using the file you sent...