A change made to fix a problem in Exchange Online introduced another problem in that service domains started to show up as prefixes in the data returned by PowerShell cmdlets. Microsoft has reversed the change, but the way things happened creates some questions.
Exchange Online now captures session identifiers in its mailbox and admin audit records that are ingested in the Office 365 audit log. That’s interesting and useful, but how do you access and interpret this information on a practical level?
You can use the Send-MailMessage cmdlet in a PowerShell script to send mail messages via Exchange Online. And sometimes your IP address might be listed as a spammer, which is bad. All in all, authenticated client submission seems best.
A question asks how to remove a bunch of emails from a shared mailbox. You can use OWA to do the job, especially with its Cleanup Mailbox option, but perhaps some administrative action is needed.
Microsoft is working on tools to move email, calendar, and contacts from G Suite to Exchange Online with availability in Q2 2019. It’s hardly a surprise.