PowerShell remote PC shutdown, single PC - powershell

Question

OU=_ is a private company name. I know it's restart, this is only for testing before it goes into the real hutdown process.
function Get-LastBootUpTime {
param (
$ComputerName
)
$OperatingSystem = Get-WmiObject Win32_OperatingSystem -ComputerName $ComputerName
[Management.ManagementDateTimeConverter]::ToDateTime($OperatingSystem.LastBootUpTime)
}
$Days = -0
$ShutdownDate = (Get-Date).adddays($days)
$ComputerList = Get-ADComputer -SearchBase 'OU=TEST-OU,OU=_,DC=_,DC=_' ` -Filter '*' | Select -EXP Name
$ComputerList | foreach {
$Bootup = Get-LastBootUpTime -ComputerName $_
Write-Host "$_ last booted: $Bootup"
if ($ShutdownDate -gt $Bootup) {
Write-Host "Rebooting Computer: $_" -ForegroundColor Red
restart-Computer $Computer -Force
}
else {
Write-Host "No need to reboot: $_" -ForegroundColor Green
}
}
I'm trying to shutdown all of the PCs in my company that run longer than 2 days. The script is kind of done, but it shows an error when it comes to the point:
restart-Computer $Computer -Force
If I type instead of $Computer, $ComputerList the script shuts down every PC in that OU, even if they didnt run longer than 2 days.
So it only takes one PC to run longer than 2 days to shut down the entire company, and that's not what I want.
How can I tell the script to only turn the PCs off, when they have already run more than 2 days?

Answer 1

Your $Computer is not defined. You should use:
Restart-Computer $_ -Force
But the better approach would be to collect all of the computers that should restart in a variable and then restart them altogether. Would work much faster:
$toBeRestarted = $ComputerList | Where-Object { $ShutdownDate -gt (Get-LastBootUpTime -ComputerName $_) }
Restart-Computer $toBeRestarted -Force
You may add some more logging around if you like