Resolve SMTP mail duplicate problem when sending to multiple addresses from GSuite
GSuite accounts that are configured to send through Office 365 accounts via SMTP started sending multiple copies of the same email any time more than one domain name is sent to in a single email. For example you might send a sales update to 40 email addresses across multiple domains and each recipient will receive the same email 40 times. For further information on the issue please read this thread: https://answers.microsoft.com/en-us/outlook_com/forum/oemail-osend/multiple-copies-of-emails-sent-to-recipients-via/84cf9460-b7f4-4e6a-bf97-a115a825f369?tm=1538072613792
The only work around's are to BCC the group and put yourself in the To: field (no one gets duplicates but you) or you can take the time to log into the office365 account you are sending through and create a group email and add the email addresses you are trying to send to. This last method works with no problems but it is clunky for end users to setup so hopefully the underlying SMTP malfunction will be fixed soon.
This is an issue which should be trivial to fix and affects the workflows of thousands of busy people.
[Deleted User] commented
Hello, I have the same problem with SMTP relay !
Duplicated emails when sent via SMTP through Office 365
Yes a many people in my organization are experiencing the same problem. So please Microsoft solve it ASAP.
Yes, there are many faculty at Harvard who have this gsuite/Office 365 setup and we're all having this duplicate mail problem as well. Many of us have migrated to gmail temporarily but please do look into this issue!
I recently sent an email to colleagues at different Universities and later was told that I had sent dozens of duplicate emails so I stopped using Office365 temporarily because it was causing lots of disruption to our project. I'm just using gmail for now, however, would love to back to the combo of gsuite/office365 for a large variety of reasons.
When I searched online, this looks like an issue that large numbers of people are having in various industries and organizations. They're posting the info across a wide range of platforms and community forums (e.g., Microsoft, Google, Reddit, etc) but they're scattered. I think people are hoping that Microsoft can have a focused team resolve the issue soon!
This is an issue that many people is complaining about, please solve it...