You can use the ''Get-ChildItem'' cmdlet to retrieve the files, and the ''Where-Object'' cmdlet to filter the files based on their age. You can then use the ''Remove-Item'' cmdlet to delete the filtered files

<code powershell>
Get-ChildItem -Path C:\path\to\folder -Recurse -File | Where-Object { $_.LastWriteTime -lt (Get-Date).AddDays(-90) } | Remove-Item –Force -Verbose
</code>

<code powershell>
Get-ChildItem -Path C:\inetpub\mailroot\Badmail -Recurse -Force | Where-Object { !$_.PSIsContainer -and $_.CreationTime -lt (Get-Date).AddDays(-30) } | Remove-Item -Force -Verbose
</code>