This script creates gets the LastBootUpDate from the PC and stores it on $LBT. Compares it with the specified variable $timeSpan and if LastBootUpTime is Less or Equal to the $timeSpan the PC is considered NON-COMPLIANT. This script is backward compatible with PowerShell 2.0!

DiscoverLastBootUpTime.ps1

# ------------------------------------------------------------------------
# NAME: DiscoverLastBootUpTime.ps1
# AUTHOR: Andre @ http://blog.teksoporte.es
# DATE:06/16/2015
#
# COMMENTS: This script creates gets the LastBootUpDate from the PC and
# stores it on $LBT. Compares it with the specified variable $timeSpan
# and if LastBootUpTime is Less or Equal to the $timeSpan the PC is
# considered NON-COMPLIANT.
# This script is backward compatible with PowerShell 2.0!
#
# ------------------------------------------------------------------------
cls

$Compliance = $Null
$LBT = [System.Management.ManagementDateTimeconverter]::ToDateTime("$((gwmi  Win32_OperatingSystem -computername $env:COMPUTERNAME).LastBootUpTime)")
$TimeSpan = (get-date).AddDays(-2)

if ($LBT -le $TimeSpan ) {
    $Compliance = "NON-COMPLIANT"
    } else {
    $compliance = "COMPLIANT"
    }
$Compliance