When you are using Office365, you may find that external email addresses in a distrbution list do not recieve mails sent to the distribution list email address.

Many spam filters will block emails with a blank or empty return path, but Office365 sets this blank as default, to prevent email bounce loops.

This is normal behaviour - a large distribution list shouldn't distribute a bounce/DSN report to the entire membership.

For a single membership list for use with Zendesk, Help Scout or other similar mailbox monitoring applications, it may be necessary.

Here is how to enable the return path for a distribution list:

Connect to Office365 with PowerShell: $LiveCred = Get-Credential $Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/powershell/ -Credential $LiveCred -Authentication Basic -AllowRedirection Import-PSSession $Session

Check to see which return paths are enabled/disabled: Get-DistributionGroup <Name Of DL> | fl *report*

When running this command, you should see: ReportToManagerEnabled : False ReportToOriginatorEnabled : False

Enable return path to originator if disabled: Set-DistributionGroup <Name Of DL> -ReportToOriginatorEnabled $true

When the command is run again: Get-DistributionGroup <Name Of DL> | fl *report*

You should see: ReportToManagerEnabled : False ReportToOriginatorEnabled : True

Disconnect from the Office365 server: Remove-PSSession $Session exit

You will then have a populated return-path (with the email address of the distribution list).