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I "own" several outlook groups. Whenever I send a message to any one of them, I guess a message similar to this one:
"Delivery has failed to these recipients or groups:
******@outlook.com A communication failure occurred during the delivery of this message. Please try to resend the message later. If the problem continues, contact your email admin.
The following organization rejected your message: CO1PEPF000075F4.mail.protection.outlook.com."
Although the email message goes through, gettings these delivery notifications freak out some users.
What is going on? This just started in the past few months.
Thanks.
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Thank you for your reply. For Outlook.com groups, open People, select the group, then check Members and remove any invalid or outdated addresses. Then send a test email to a few members instead of the full group. If the error stops, add members back in batches to find the address causing rejection. This isolates the failing recipient so the server no longer returns a failed delivery notice.
Is this email address one of them in the group? If so, this is not a legitimate outlook.com email address. It is a placeholder address for someone who has a Microsoft account, but uses a third party non Microsoft address as their Microsoft account alias. If they try to send out email from outlook.com, Microsoft will use this placeholder email to send it, but it is not meant to receive inbound emails. Remove this email address from your group list, see if it works better.
This is not the address of anyone in the group.
Ok, thanks for checking.
In this case, please complete these steps on a computer, not on a smartphone or tablet.
====================
First, go to https://www.outlook.com and sign in.
Click the gear icon in the top right corner to open Settings.
Under Mail, review the following areas:
Rules
If any rules are listed, delete all of them.
Conditional formatting
If anything is set up there, delete it.
Forwarding and IMAP
If you see any entries or settings you did not create, remove them. Turn off POP and IMAP.
Junk
Review Safe sender and blocked list. If you don't recognize any, remove them.
Unfortunately, none of those things were applicable. Thanks, though.
You said the notification freaked out some users. Did they receive such notification on their end, or did you receive it on your end?
Anyone who posts to a list gets the message. It's very weird.
Ask everyone in the list to check their mailbox rules settings. I believe one of you have their mailbox set up to forward to that odd looking email address in my screenshot, hence everyone who replies, it delivers to everyone, but the auto-forward to that odd email hits a snag.
Hello, does this happen with every group or only one specific group?
Open Outlook on the web, go to People, select the group, then Settings. Check Delivery management and turn on allow external senders, then review Message approval and remove any moderation. Also open the member list and remove any invalid or outdated addresses. This stops partial rejection by the mail server and removes the failure notice.
"Delivery management" setting is not available. I'm not a sys admin; I'm just a regular user that created a group.
