Get-SID

function Get-SID
{
  [CmdletBinding()]
  param
  (
    [Parameter(Mandatory=$true, Position=0)]
    [System.Object]$user
  )
  Try {
    $domain = $env:USERDOMAIN
    $objUser = New-Object System.Security.Principal.NTAccount("$domain","$user") -ErrorAction Stop
    $strSID = $objUser.Translate([System.Security.Principal.SecurityIdentifier])
    $strSID.Value
    Write-Host
  }
  Catch {
    Write-Error -Message 'Failed to get user SID.'
  }
}