Remove AD computers

<##
Usage : This script can be run as a standalone task on a schedule or called manually, using the set variables in the first section
Purpose : Find all non-server Windows computer accounts in the domain that have not communicated with a domain controller and remove them.
Author : Liam@liveitcg.com
##>
$maxage = 90   ## Maximum days a computer can not check in with a domain controller before it is considered stale and deleted
$file = 'C:\temp\deletedcomputers.csv'  ## temp location for email attachment ; directory must exist
$emailTo = "Your Name <email@domain.com>" ## add multiple quoted entries separated by comma
$mailserver = "outlook.office365.com"  ## SMTP relay server
$remove = $false ## set this to $true to delete objects ; set this to $false to just generate an email report


### Don't modify below this line
$daysold = (get-date).adddays(-$maxage)
## Query for computers that have not logged in
$oldcomputers=Get-ADComputer -Filter {lastlogondate -lt $daysold -and operatingsystem -like "Windows*" -and operatingsystem -notlike "*Server*"}  -Properties lastlogondate,operatingsystem,canonicalname |sort lastlogondate
$oldcomputers | select name, LastLogonDate, operatingsystem, canonicalname |export-csv -NoTypeInformation -Path $file

if ($remove) {
## Purge computers
$oldcomputers| Remove-ADObject -Recursive -Confirm:$false
## Re-Query to find any computers that were not removed after 3 min cool off
Sleep -seconds 180
$failed=Get-ADComputer -Filter {lastlogondate -lt $daysold -and operatingsystem -like "Windows*" -and operatingsystem -notlike "*Server*"}  -Properties lastlogondate,operatingsystem,canonicalname |sort lastlogondate

## Retry loop if there are any objects found that should have been removed.
## Retry 3 times ; 3 minute cool off interval
$i=0;   while ($failed.length -gt 0 -and $i -lt 3) {
        $failed | Remove-ADObject -Recursive -Confirm:$false
        sleep -seconds 180
        $failed=Get-ADComputer -Filter {lastlogondate -lt $daysold -and operatingsystem -like "Windows*" -and operatingsystem -notlike "*Server*"}  -Properties lastlogondate,operatingsystem,canonicalname |sort lastlogondate
        $i++
    }
## Report if query still finds objects that were not removed
if ($failed.length -gt 0) {$blob += "There were "+($failed.length)+" accounts that were not removed." ; $failed.name |%{$blob+=$_;$blob+="`r`n"}; $blob += "`r`n"}

##  Build email notification body
$blob += "There were "+($oldcomputers.length)+" computers removed.`r`n"
$blob += "List of computers deleted.`r`n"
$oldcomputers.name |%{$blob+=$_;$blob+="`r`n"}
    }
##  Build email notification for report only
else {
$blob += "There are "+($oldcomputers.length)+" stale computers in the domain.`r`n"
$blob += "List of computers that can be deleted.`r`n"
$oldcomputers.name |%{$blob+=$_;$blob+="`r`n"}
}
Send-MailMessage -To $emailTo -From "Computer cleanup script <noreply@domain.com>" -Subject "AD Computer desktop cleanup" -SmtpServer $mailserver -Body $blob -Attachments $file

remove-item $file