Add-LocalGroupMember

Add-LocalGroupMember.ps1

function Add-LocalGroupMember {
<#
	.SYNOPSIS
        Adds AD user to Local Computer Group
    
    .PARAMETER  ComputerName
        Name of Local Computer(s) where group resides

    .PARAMETER  Groups
        Name of Local Group where user will be added
    
    .PARAMETER  Members
        Name of User(s) to be added to specified group

    .PARAMETER  Credential
        Credential in which command will be run
       
    .EXAMPLE
        Add-LocalGroupMember -ComputerName Server1 -Group "Backup Operators" -Members jsmith

        This commmand adds User 'jsmith' to the Local Backup Operators group on Server1
    
    .EXAMPLE
        Add-LocalGroupMember -ComputerName Server1 -Group "Backup Operators","Administrators' -Members mydomain\jsmith

        This commmand adds mydomain\jsmith to the Local Backup Operators and Administrators group on Server1

    .EXAMPLE
        Add-LocalGroupMember -ComputerName Server1 -Group "Backup Operators" -Members 'jsmith','mydomain\bjohn','twalter@domain.com' -Credential $myCred

        This commmand adds 'jsmith','mydomain\bjohn', and 'twalter@domain.com' to the Local Backup Operators group on Server1 using provided credentials
        
        NOTE: Multiple Connections to a server using more than one user account is not allowed. Will not work if the current system has a connection to the server using different credentials than the ones specified

    .INPUTS
#>

    [CmdletBinding(SupportsShouldProcess=$true)]
    param (
        [parameter(Mandatory=$false)]
        [string[]]$ComputerName = "localhost",

        [parameter(Mandatory=$true)]
        [string[]]$Groups,
     
        [parameter(Mandatory=$true)]
        [string[]] $Members,
        
        [System.Management.Automation.CredentialAttribute()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )
    
    begin {}
    process {

        foreach($computer in $ComputerName){
            foreach($group in $Groups) {
                foreach($member in $Members) {

                    #Write-Progress "Adding $domain\$Username to the local $Group group on $computer"

                    # Bind Local Server Group
                    if($Credential -ne [System.Management.Automation.PSCredential]::Empty){
                        $currentGroup = New-Object -TypeName System.DirectoryServices.DirectoryEntry -ArgumentList "WinNT://$computer/$group,group",$($Credential.UserName),$($Credential.GetNetworkCredential().password) -ErrorAction Stop
                    }
                    else{
                        $currentGroup = [ADSI]"WinNT://$computer/$group,group";
                    }
        
                
                    # Determine Username and Domain
                    if($member -like "*@*"){
                        $split = $member.Split("@")
                    
                        $username = $split[0]
                        $domain = $split[1]
                    }
                    elseif($member -like "*\*"){
                        $split = $member.Split("\")
                    
                        $username = $split[1]
                        $domain = $split[0]
                    }
                    else{
                        $username = $member
                        $domain = $env:COMPUTERNAME
                    }
                
                    # Bind to user
                    $user = [ADSI]"WinNT://$domain/$username,user";


                    # Add AD security group to Local Server Group
                    try{
                        $currentGroup.Add($user.Path);
                    }
                    catch{
                        $errorMessage = $_.Exception
                        if (([string]$errorMessage).Contains("Multiple connections to a server")){
                            Write-Warning "Multiple Connections to a server using more than one user account is not allowed"
                            Write-Warning "Please try again without Credential parameter"
                            Throw "Failed to add user to group"
                        }
                        else {Write-Error -Exception $errorMessage}
                    }
                } # foreach - Members
            } # foreach - Groups
        } # foreach - Computers
    } # Process
    End {
    }
}