DROP : Reason: [{LED=250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded};{MSG=};{FQDN=};{IP=};{LRT=}]

_{Monday, July 1, 2019 3:21 PM}

I have scenario where some of our users is sending email to a DL from a shared mailbox and its not getting delivered. Shared mailbox has all delegation and permissions to send to the DL

When ran a trace report from O365 getting this event

DROP : Reason: [{LED=250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded};{MSG=};{FQDN=};{IP=};{LRT=}]

I would like to know the root cause of this DROP. Where should i find it. How it needs to be rectified. I did open case with MS but pending there research. Users used to be able to send to this DL and expand to see "Members" now they cannot.

_{Monday, July 1, 2019 8:55 PM ✅Answered}

Here is the fix, essentially you need to  add the shared mailbox as a listing to bypass moderation of the DL, to do this by Powershell: 

Set-DistributionGroup “<name>” -ByPassModerationFromSendersOrMembers @{Add="<recipient1>","<recipient2>"}<o:p></o:p>

_{Monday, July 1, 2019 4:21 PM}

I have scenario where some of our users is sending email to a DL from a shared mailbox and its not getting delivered. Shared mailbox has all delegation and permissions to send to the DL

When ran a trace report from O365 getting this event

DROP : Reason: [{LED=250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded};{MSG=};{FQDN=};{IP=};{LRT=}]

I would like to know the root cause of this DROP. Where should i find it. How it needs to be rectified. I did open case with MS but pending there research. Users used to be able to send to this DL and expand to see "Members" now they cannot.

DROP only means the list was expanded, not that the message itself was dropped.

Search by MessageID instead.

If all else fails, recreate the group.

_{Monday, July 1, 2019 7:05 PM}

thanks but this just started to not work. I'll see what MS has to say, and thank you for feedback.

_{Tuesday, July 2, 2019 2:31 AM}

Thanks for your sharing!

Regards,

Manu Meng

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