Update an AWS IAM Policy using PowerShell

#Json file preparation & adding new email address
Add-Type -AssemblyName Microsoft.VisualBasic

# Set file name
$File = '\\Fileserver\aws$\LinuxDev_PolicyUpdate\NewPolicyVersion.json'
$NewEmail = [Microsoft.VisualBasic.Interaction]::InputBox('Enter email address to add to AWS', 'Email address')
$collate = foreach($Obj in $NewEmail) {       
    $begin = '                        "'
    $end = '",'
    $begin + $Obj + $end

    }


# Process lines of text from file and assign result to $NewContent variable
$NewContent = Get-Content -Path $File |
    ForEach-Object {
        # Output the existing line to pipeline in any case
        $_

        # If line matches regex
        if($_ -match ('^' + [regex]::Escape('                    "ses:FromAddress": [')))
        {
            # Add output additional line
            $collate
        }
    }

# Write content of $NewContent variable back to file
$NewContent | Out-File -FilePath $File -Encoding Default -Force

Start-Sleep -s 10

#AWS module - get credentials & region
import-module awspowershell

Set-AWSCredential -AccessKey 'enter accesskey' -SecretKey 'enter secretkey’

Set-DefaultAWSRegion -Region us-west-1

Start-Sleep -s 5

#Create policy version variable, sort to put oldest entry at the top and then selct it.
$PolicyVersion = Get-IAMPolicyVersionList -PolicyArn arn:aws:iam::123456789183:policy/AmazonSes_policy | Sort-Object -Property VersionId -Descending:$false | Select-Object -First 1 | Select-Object -ExpandProperty VersionID

#Remove oldest policy version
Remove-IAMPolicyVersion -PolicyArn arn:aws:iam::123456789183:policy/AmazonSes_policy -VersionId $PolicyVersion -Force

Start-Sleep -s 5

#Create new policy version importing from .json file
New-IAMPolicyVersion -PolicyArn arn:aws:iam::123456789183:policy/AmazonSes_policy /AmazonSes_LinuxDev -PolicyDocument (Get-content -Raw \\Fileserver\aws$\LinuxDev_PolicyUpdate\NewPolicyVersion.json) -SetAsDefault $true

Start-Sleep -s 5

#Send an email informing IT about the update to the policy

$emailSmtpServer = "email-smtp.us-west-1.amazonaws.com"

$emailSmtpServerPort = "587"

$emailSmtpUser = "smtp username"

$emailSmtpPass = "smtp password"

$emailMessage = New-Object System.Net.Mail.MailMessage

$emailMessage.From = "AWS SES <SESpolicyupdates@domain.com>"

$emailMessage.To.Add( "user@hotmail.com" )

$emailMessage.Subject = "New email address added to policy"

$emailMessage.IsBodyHtml = $true
$emailMessage.Body = @"

<p>Email address $NewEmail was added to the AmazonSes_policy policy.</p>
"@

$SMTPClient = New-Object System.Net.Mail.SmtpClient( $emailSmtpServer , $emailSmtpServerPort )

$SMTPClient.EnableSsl = $true

$SMTPClient.Credentials = New-Object System.Net.NetworkCredential( $emailSmtpUser , $emailSmtpPass );

$SMTPClient.Send( $emailMessage )