Many people use the PowerShell Send-MailMessage cmdlet to send email from Exchange Online. In this article, we explain how to use cmdlets from the Microsoft Graph SDK for PowerShell to do the same job. The reason why this is important is that Microsoft will eventually deprecate the Send-MailMessage cmdlet as part of its campaign to eliminate basic authentication from Exchange Online. A replacement will be needed for all those PowerShell scripts which uses Send-MailMessage. This is one solution.
https://practical365.com/send-mail-exchange-online-graph-powershell/
