Microsoft 365 License Monitoring and Alert Script

# Uncomment and install MSAL.PS and Microsoft.Graph PowerShell modules, skip if already installed 
# Install-Module -Name MSAL.PS
# Install-Module -Name Microsoft.Graph

Import-Module Microsoft.Graph.Users
Import-Module MSAL.PS

# Set variables
$tenantId = "replace_with_value"
$clientId = "replace_with_value"
$clientSecret = "replace_with_value"
$emailSender = "sharedmailbox@contoso.com"
$emailRecipients = @("user1@contoso.com", "user2@contoso.com", "DL.Name@contoso.com")
$emailSubject = "Microsoft 365 - Low License Alert"

# Convert client secret to secure string
$clientSecretSecure = ConvertTo-SecureString -String $clientSecret -AsPlainText -Force

# Use the secure string in Get-MsalToken
$tokenResponse = Get-MsalToken -ClientId $clientId -ClientSecret $clientSecretSecure -TenantId $tenantId -Scopes "https://graph.microsoft.com/.default"

# Get an OAuth 2.0 token
$accessToken = $tokenResponse.AccessToken

# Get the list of SKUs with less than 5 licenses left for specified SKUs
$uri = "https://graph.microsoft.com/v1.0/subscribedSkus"
$response = Invoke-RestMethod -Uri $uri -Method GET -Headers @{ Authorization = "Bearer $accessToken" }

$copilot = $response.value | Where-Object {($_.skuPartNumber -eq "Microsoft_365_Copilot")}
$e3 = $response.value | Where-Object {($_.skuPartNumber -eq "SPE_E3")}
$e1 = $response.value | Where-Object {($_.skuPartNumber -eq "STANDARDPACK")}
$defender1 = $response.value | Where-Object {($_.skuPartNumber -eq "ATP_ENTERPRISE")}

$copilotAvailableUnits = $copilot.prepaidUnits.enabled - $copilot.consumedUnits
$e3AvailableUnits = $e3.prepaidUnits.enabled - $e3.consumedUnits
$e1AvailableUnits = $e1.prepaidUnits.enabled - $e1.consumedUnits
$defender1AvailableUnits = $defender1.prepaidUnits.enabled - $defender1.consumedUnits

# If there are SKUs with less than 5 licenses left, send an email
if (($copilotAvailableUnits -le 5) -or ($e3AvailableUnits -le 5) -or ($e1AvailableUnits -le 5) -or ($defender1AvailableUnits -le 5)) {
    $emailBody = "<html><body><table border='1'><tr><th>SKU Name</th><th>Total License Count</th><th>Total License Used</th><th>Total Available License Count Left</th></tr>"
    $emailBody += "<tr><td>Microsoft_365_Copilot</td><td>$($copilot.prepaidUnits.enabled)</td><td>$($copilot.consumedUnits)</td><td>$($copilotAvailableUnits)</td></tr>"
    $emailBody += "<tr><td>Microsoft 365 E3</td><td>$($e3.prepaidUnits.enabled)</td><td>$($e3.consumedUnits)</td><td>$($e3AvailableUnits)</td></tr>"
    $emailBody += "<tr><td>Office 365 E1</td><td>$($e1.prepaidUnits.enabled)</td><td>$($e1.consumedUnits)</td><td>$($e1AvailableUnits)</td></tr>"
    $emailBody += "<tr><td>Microsoft Defender Plan 1</td><td>$($defender1.prepaidUnits.enabled)</td><td>$($defender1.consumedUnits)</td><td>$($defender1AvailableUnits)</td></tr>"
    $emailBody += "</table></body></html>"

    # Create the email message
    $emailMessage = @{
        Message = @{
            Subject = $emailSubject
            Body = @{
                Content = $emailBody
                ContentType = "HTML"
            }
            ToRecipients = @(
                $emailRecipients | ForEach-Object {
                    @{
                        EmailAddress = @{
                            Address = $_
                        }
                    }
                }
            )
        }
        SaveToSentItems = "true"
    }

    # Send the email
    $response = Invoke-RestMethod -Uri "https://graph.microsoft.com/v1.0/users/$emailSender/sendMail" `
                                  -Method POST `
                                  -Headers @{ Authorization = "Bearer $accessToken" } `
                                  -Body (ConvertTo-Json $emailMessage -Depth 100) `
                                  -ContentType "application/json"

    Write-Output "Email sent successfully"
}
else {
    Write-Output "No SKUs with less than 5 licenses left"
}