Check for certificate expiration with PowerShell (on multiple servers)

One of my clients asked me how to check for expired certificates. This simple script opens the certificate store through the PS-drive CERT: and lists all certificates that are soon to expire. You can change the threshold to any value in the first line. Here’s the script:

$threshold = 30   #Number of days to look for expiring certificates
$deadline = (Get-Date).AddDays($threshold)   #Set deadline date
Dir Cert:\LocalMachine\My | foreach {
If ($_.NotAfter -le $deadline) { $_ | Select Issuer, Subject, NotAfter, @{Label="Expires In (Days)";Expression={($_.NotAfter - (Get-Date)).Days}} }
}

This script can also be used for several machines at once. Just add the Invoke-Command to the Dir command and make sure PowerShell remoting has been set up by using Enable-PSRemoting on the target servers. More info by running this PowerShell command: Get-Help about_remoting.

$threshold = 30   #Number of days to look for expiring certificates
$deadline = (Get-Date).AddDays($threshold)   #Set deadline date
Invoke-Command -ComputerName Srv01, Srv02 { Dir Cert:\LocalMachine\My } | foreach {
If ($_.NotAfter -le $deadline) { $_ | Select Issuer, Subject, NotAfter, @{Label="Expires In (Days)";Expression={($_.NotAfter - (Get-Date)).Days}} }
}

Dimitri