9to5IT

Import-Module ActiveDirectory

# Set the number of days since last logon
$DaysInactive = 90
$InactiveDate = (Get-Date).Adddays(-($DaysInactive))

#-------------------------------
# FIND INACTIVE COMPUTERS
#-------------------------------
# Below are three options to find inactive computers. Select the one that is most appropriate for your requirements:

SMSAgentSoftware

[CmdletBinding(DefaultParameterSetName='All')]
Param
(
    [Parameter(ParameterSetName='All',Mandatory=$true,ValueFromPipelineByPropertyName=$true,ValueFromPipeline=$true)]
    [Parameter(ParameterSetName='Individual',Mandatory=$true,ValueFromPipelineByPropertyName=$true,ValueFromPipeline=$true)]
    [string[]]$ComputerName,
    [Parameter(ParameterSetName='All')]
    [switch]$All = $True,
    [Parameter(ParameterSetName='Individual')]
    [switch]$AD,