Powershell Send-MailMessage Authentication

If you are looking for a way to send email from PowerShell, then you may have come across the Send-MailMessage cmdlet. This is a great way to send email messages, but you may run into issues with authentication.

Authentication

In order to send email through Send-MailMessage, you need to have proper authentication. This means that you need to have the correct username and password for the email server that you are using. If you do not have the correct authentication information, then you will not be able to send email messages.

Using SMTP Authentication

There are a couple of ways to provide authentication information to Send-MailMessage. One way is to use SMTP authentication. This requires you to provide a username and password for the email server that you are using. Here is an example of how to send an email with SMTP authentication:

$smtpServer = "smtp.gmail.com"
$port = "587"
$username = "your.username@gmail.com"
$password = "yourpassword"
$to = "recipient@example.com"
$subject = "Test email"
$body = "This is a test email sent via PowerShell"
Send-MailMessage -From $username -To $to -Subject $subject -Body $body -SmtpServer $smtpServer -Port $port -UseSsl -Credential (New-Object System.Management.Automation.PSCredential $username,(ConvertTo-SecureString $password -AsPlainText -Force))

In this example, we are using Gmail's SMTP server to send the email message. We are also using port 587, which is commonly used for TLS connections.

Using OAuth2 Authentication

Another way to provide authentication information is to use OAuth2 authentication. This requires you to generate an access token using OAuth2. Here is an example of how to send an email with OAuth2 authentication:

$smtpServer = "smtp.gmail.com"
$port = "587"
$clientId = "your-client-id.apps.googleusercontent.com"
$clientSecret = "your-client-secret"
$refreshToken = "your-refresh-token"
$to = "recipient@example.com"
$subject = "Test email"
$body = "This is a test email sent via PowerShell"
$scopes = "https://www.googleapis.com/auth/gmail.send"
$cred = Get-GmailOAuthCredential -ClientId $clientId -ClientSecret $clientSecret -RefreshToken $refreshToken -Scopes $scopes
Send-GmailMessage -To $to -Subject $subject -Body $body -IsHtml -Credential $cred

In this example, we are using OAuth2 authentication to send the email message. We are using the Get-GmailOAuthCredential function from the PowerShellGallery to retrieve an OAuth2 access token.

Conclusion

Sending email from PowerShell can be a useful tool, but it requires proper authentication. Using either SMTP or OAuth2 authentication, you can send email messages from PowerShell with ease.