<#
  This script will enumerate all user accounts in a Domain, and report
  on the following attributes:

  Script Name: Get-UserReport.ps1
  Release 1.0
  Written by [email protected] 27/12/2013

#>

#-------------------------------------------------------------

# Set this value to true if you want to see the progress bar.
$ProgressBar = $True

# Set this to true to process disabled user accounts.
$ProcessDisabledUsers = $True

#-------------------------------------------------------------

# Get the script path
$ScriptPath = { Split-Path $MyInvocation.ScriptName }
$ReferenceFile = $(&$ScriptPath) + "\UserReport.csv"

$array = @()
$primarygroups = @{}
$TotalUsersProcessed = 0
$UserCount = 0

$ADRoot = ([System.DirectoryServices.DirectoryEntry]"LDAP://RootDSE")
$DefaultNamingContext = $ADRoot.defaultNamingContext

# Derive FQDN Domain Name
$TempDefaultNamingContext = $DefaultNamingContext.ToString().ToUpper()
$DomainName = $TempDefaultNamingContext.Replace(",DC=", ".")
$DomainName = $DomainName.Replace("DC=", "")

if ($ProcessDisabledUsers -eq $False) {
    # Create an LDAP search for all enabled users not marked as criticalsystemobjects to avoid system accounts
    $ADFilter = "(&(objectClass=user)(objectcategory=person)(!userAccountControl:1.2.840.113556.1.4.803:=2)(!(isCriticalSystemObject=TRUE))(!name=IUSR*)(!name=IWAM*)(!name=ASPNET))"
}
else {
    # Create an LDAP search for all users not marked as criticalsystemobjects to avoid system accounts
    $ADFilter = "(&(objectClass=user)(objectcategory=person)(!(isCriticalSystemObject=TRUE))(!name=IUSR*)(!name=IWAM*)(!name=ASPNET))"
}
# There is a known bug in PowerShell requiring the DirectorySearcher
# properties to be in lower case for reliability.
$ADPropertyList = @("distinguishedname", "samaccountname", "objectsid", "primarygroupid")
$ADScope = "SUBTREE"
$ADPageSize = 1000
$ADSearchRoot = New-Object System.DirectoryServices.DirectoryEntry("LDAP://$($DefaultNamingContext)")
$ADSearcher = New-Object System.DirectoryServices.DirectorySearcher
$ADSearcher.SearchRoot = $ADSearchRoot
$ADSearcher.PageSize = $ADPageSize
$ADSearcher.Filter = $ADFilter
$ADSearcher.SearchScope = $ADScope
if ($ADPropertyList) {
    foreach ($ADProperty in $ADPropertyList) {
        [Void]$ADSearcher.PropertiesToLoad.Add($ADProperty)
    }
}
$colResults = $ADSearcher.Findall()
$UserCount = $colResults.Count

if ($UserCount -ne 0) {
    foreach ($objResult in $colResults) {
        $lastLogonTimeStamp = ""
        $lastLogon = ""
        $UserDN = $objResult.Properties.distinguishedname[0]
        $samAccountName = $objResult.Properties.samaccountname[0]

        # Get user SID
        $arruserSID = New-Object System.Security.Principal.SecurityIdentifier($objResult.Properties.objectsid[0], 0)
        $userSID = $arruserSID.Value

        # Get the SID of the Domain the account is in
        $AccountDomainSid = $arruserSID.AccountDomainSid.Value

        # Get Primary Group by binding to the user account
        $objUser = [ADSI]("LDAP://" + $UserDN)
        $primarygroupID = $objUser.primarygroupid
        if ($null -ne $primarygroupID) {
            # Primary group can be calculated by merging the account domain SID and primary group ID
            $primarygroupSID = $AccountDomainSid + "-" + $primarygroupID.ToString()
            $primarygroup = [adsi]("LDAP://<SID=$primarygroupSID>")
            $primarygroupname = $primarygroup.name[0]
            $objUser = $null
        }
        else {
            $primarygroupname = "NULL"
        }

        # Create a hashtable to capture a count of each Primary Group
        if (!($primarygroups.ContainsKey($primarygroupname))) {
            $primarygroups = $primarygroups + @{$primarygroupname = 1 }
        }
        else {
            $value = $primarygroups.Get_Item($primarygroupname)
            $value ++
            $primarygroups.Set_Item($primarygroupname, $value)
        } # end if

        $TotalUsersProcessed ++
        if ($ProgressBar) {
            Write-Progress -Activity 'Processing Users' -Status ("Username: {0}" -f $samAccountName) -PercentComplete (($TotalUsersProcessed / $UserCount) * 100)
        }
    }
    Write-Host -ForegroundColor Green "`nA breakdown of the $($primarygroups.count) Primary Groups applied to $TotalUsersProcessed user objects:"
    $primarygroups.GetEnumerator() | Sort-Object Name | ForEach-Object {
        Write-Host -ForegroundColor Green "- $($_.key): $($_.value)"
    }
}