function Get-ADUserLastLogon($userName)

{

$dcs = Get-ADDomainController -Filter {Name -like "*"}

$time = 0

foreach($dc in $dcs)

{

$hostname = $dc.HostName

$user = Get-ADUser $userName -Server $hostname | Get-ADObject -Properties lastLogon

if($user.LastLogon -gt $time)

{

$time = $user.LastLogon

}

}

$dt = [DateTime]::FromFileTime($time)

Write-Host $username.samaccountname "last logged on at:" $dt

}

$Groups = Get-ADGroup -Filter {Name -like "fi*"}

$groupmembers = @()

ForEach ($Group in $Groups) {

    $groupmembers += (Get-ADGroupMember -Identity "$($Group.Name)"  -Recursive)

}

$groupmembers = $groupmembers|select  -Unique

foreach($account in $groupmembers)

{

Get-ADUserLastLogon -UserName $account

}