We have an on-premises Exchange 2013 deployment that just went live after a big migration this past weekend. Plenty of the usual, and perhaps some not-so-usual, hiccups, but one that has me particularly stumped is that when my users mark a message as junk in OWA and select "Report" when they are prompted to report it to Microsoft, they eventually get their report bounced back to them with an NDR similar to the following:

Delivery has failed to these recipients or groups:
junk@senpluspluseop.onmicrosoft.com
A problem occurred during the delivery of this message. Please try to resend the message later.

The following organization rejected your message: BN3NAM01FT005.mail.protection.outlook.com.

Diagnostic information for administrators:
Generating server: BY2NAM01HT014.mail.protection.outlook.com
junk@senpluspluseop.onmicrosoft.com
BN3NAM01FT005.mail.protection.outlook.com
Remote Server returned '<BN3NAM01FT005.mail.protection.outlook.com #5.4.14 smtp;554 5.4.14 Hop count exceeded - possible mail loop ATTR1>'

I've been unable to determine why these reports would be being sent to an address that evidently doesn't work. Is this because we do not have Exchange Online Protection? Should we turn off the "Report" feature altogether as a result?

As far as I know, the junk reporting option only applies to orgs that are also using EOP.

You can of course send a message with the attached messages directly to:

junk@office365.microsoft.com

but that doesnt add any value for your org if you arent using EOP.

That's what I had begun to suspect, thanks for the confirmation.

Hello,

Yes, the Junk Email Reporting Add-in helps you submit reports to the Microsoft Exchange Online Protection (EOP) service:

https://technet.microsoft.com/en-us/library/jj723151(v=exchg.150).aspx

 

Thanks,

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