I'm troubleshooting an issue where a user, [email protected], is receiving emails sent to a group ([email protected]) that they aren't a part of. I've double-checked a few things: jdoe is definitely not a member of the sales group or any related groups, there are no transport rules affecting this, and I can't find any record of these emails being sent to jdoe in Exchange Online. We're using Mimecast for mail filtering. What's puzzling is that jdoe used to be in the sales group earlier this year, but has since transitioned to another group ([email protected]). Any insights or suggestions would be greatly appreciated!
2 Answers
Could be an issue with SMTP aliases. Check the attributes for jdoe's account in Active Directory. Sometimes, shared mailboxes or alias collisions can cause unexpected email delivery.
It sounds like the emails could be routed through Mimecast, possibly due to redirect or journaling rules. I'd recommend checking the full email headers and Mimecast's delivery logs to determine the actual envelope recipients. That should give you more clues about where these emails are coming from and why they’re reaching jdoe.
Yeah, definitely check the SMTP address and proxy settings. That might shed some light on the situation.