Emails to distribution list being dropped

[dan-o365]

Emails have just been dropped with no NDR. These are internal users messaging an internal distribution group. The support tech had no idea, and refused to escalate the case. When I did a message trace this is the error I got

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

Is there a way to escalate cases? I've heard nothing in over a day even after requesting an update.

[#2]

That message is perfectly normal for emails sent to DLs, post the full message trace.

[#3]

@Vasil Michev 

Jun 4, 2019 4:00:22 PM

Receive

Message received by: DM5PR06MB2345 using TLS1.2 with AES256

Jun 4, 2019 4:00:22 PM

Submit

The message was submitted.

Jun 4, 2019 4:00:22 PM

Expand DL

The message was sent to a distribution list (DL) that was expanded to the recipients of the DL.

Jun 4, 2019 4:00:22 PM

Drop

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

Jun 4, 2019 4:00:22 PM

Spam Diagnostics

 More information

Message ID:

<3FEF1E44-806D-4462-AA96-BC6329B700DC@****.com>

Message size:

48 KB

From IP:

50.243.147.228

To IP:

[#4]

You need the message trace details, Get-MessageTraceDetail. And you can also check the traces to the individual recipients, especially the ones that are having issues receiving messages.

[#5]

@Vasil Michev 

Where in office 365 am I allowed to use Exchange cmdlets?

[#6]

Nowhere, use PowerShell: https://docs.microsoft.com/en-us/powershell/exchange/exchange-online/connect-to-exchange-online-powe...

[#7]

@Vasil Michev The problem is not all of us are Powershell users and prefer a GUI as we don't have time to learn Powershell. Having just moved from Google to Microsoft 365 I can already see how easy Google's system is in comparison. Having to use Powershell for some things in Microsoft 365 is fine for seasoned IT Pros but not for those of us that have never use Exchange before. So far I'm not impressed with the admin experience of using Microsoft 365 compared to Google Workspace.

[#8]

- you can do a detailed trace report from the admin center..
https://admin.exchange.microsoft.com/#/messagetrace
- If the group includes nested groups that are synced from your on premises Active Directory, check that the groups are mail enabled and has an email address.

[#9]

Since I posted my reply I've had more time to live with the Admin center. I've even done some email tracing using it already. Incidentally, I came to this post because I was getting a similar issue. However, my trouble turned out to be that I had actually forgotten to add any email addresses to the Distributon Group after I created it. LOL.