Find Expiring Certificates in Local Computer Personal Store

I originally wrote this as a monitor for SolarWinds. I'm posting it here as it could also be used to do a foreach against an OU, csv, etc. Basically, search through the computer personal certificate store and return the certs that expire in X days.

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Import-Module WebAdministration
$Certificates = dir Cert:\localmachine\my
$today = get-date
$expirationcounter = 0

foreach ($cert in $Certificates)
{
    $thumbprint = $Cert.Thumbprint;
    $certdetails = Get-ChildItem Cert:\LocalMachine\my\$thumbprint | Select NotAfter,Subject,Issuer;

    if($certdetails.notafter -lt $today.AddDays(60))
    {
        $expiresin = $certdetails.NotAfter - $today
        Write-Host "Statistic:" $expiresin.days
        Write-Host 'Message: ' $certdetails.Subject
        $expirationcounter++
    }
}

if($expirationcounter -eq 0)
{
    Write-Host 'Statistic: ' 0
    Write-Host 'Message: No Certificates Found'
}
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