Pasted

Function Global:Set-LocalAdminGroupMembership
{
 
 
    <#
    .Synopsis
 
    .Description
 
    .Parameter $ComputerName,
 
    .Example
     PS> Set-LocalAdminGroupMembership -ComputerName $ComputerName -Account 'YourAccount'
//youraccount will usually be set as 'guest' while running this script
    .Link
     about_functions
     about_functions_advanced
     about_functions_advanced_methods
     about_functions_advanced_parameters
 
    #>
 
 
 
    [CmdletBinding()]
    param(
    [Parameter(Position=0, ValueFromPipeline=$true)]
    $ComputerName = '.',
    [Parameter(Position=1, Mandatory=$true)]
    $Account
    )
 
 
    Process
    {  
 
        if($ComputerName -eq '.'){$ComputerName = (get-WmiObject win32_computersystem).Name}    
        $ComputerName = $ComputerName.ToUpper()
 
 
        $Domain = $env:USERDNSDOMAIN
 
        if($Domain){
            $adsi = [ADSI]"WinNT://$ComputerName/administrators,group"
            $adsi.add("WinNT://$Domain/$Account,group")
            }else{
            Write-Host "Not connected to a domain." -foregroundcolor "red"
            }
 
 
    }# Process
 
 
}# Set-LocalAdminGroupMembership