Error: [501.5.1.8 Your message couldn't be delivered because the email has no mail from address]

There are settings for distribution lists and mail-enabled security groups that determine where non-delivery reports for emails sent to the group should be delivered. These settings affect the mail from address on the email.

These settings are:

• ReportToOriginatorEnabled
• ReportToManagerEnabled

For an email sent to a group to route correctly through Exclaimer Cloud, the ReportToOriginatorEnabled property needs to be set to True.

If ReportToManagerEnabled is set to True, the email will still route correctly; however, a signature will be applied for the sender's manager, therefore the ReportToManagerEnabled should be set to False.

NOTE: By default, a group created in Exchange Online will have ReportToOriginatorEnabled set to True.

If the group is synchronized from Active Directory then set ReportToOriginatorEnabled to true:

1. Open Active Directory Users and Computers.
   
   
2. Navigate to the View menu and select Advanced Features. 
   
   
   
   
3. Navigate to the group in your directory.
   
   
4. Open the group properties (you can either right-click the Properties or double-click the group).
   
   
5. Open the Attribute Editor tab.
   
   
6. Scroll down to reportToOriginator.
   
   
7. Click Edit.
   
   
8. Set the value to True.
   
   
   
   
9. In the Boolean Attribute Editor window, click OK. 
   
   
10. In the Properties window, click OK.

If the group is Microsoft 365 only (not synchronized from Active Directory) then set ReportToOriginatorEnabled to true using PowerShell

Install Exchange Online PowerShell V2 module:

1. Open the Windows PowerShell and run this command as an Administrator:
   
   Install-Module -Name ExchangeOnlineManagement
2. Confirm that you want to install this PowerShell module.
   NOTE: For additional installation options, see ExchangeOnlineManagement.

Connect to Exchange Online:

• Run this command:
  
  Connect-ExchangeOnline -UserPrincipalName <UPN> -ShowProgress $true
  When prompted, enter your password (and the Multi-Factor Authentication verification code if required).

To check the ReportToOriginatorEnabled property for a specific group:

• Run the following command:
  
  Get-DistributionGroup <Group Email Address> | fl ReportToOriginatorEnabled
  
  Where <Group Email Address> is replaced with the email address for the affected group
  
• If the value returned is False, run this command to change it to True: 
  
  Set-DistributionGroup <Group Email Address> -ReportToOriginatorEnabled $true
  
  Where <Group Email Address> is replaced with the email address for the affected group
  
  NOTE: If you see an error stating that the group must not report to both the manager and the originator like below: 
  

  Set-DistributionGroup: Ex9A45AC|Microsoft.Exchange.Data.DataValidationException|The group "<Group Name>" must not report to both
  the manager and the originator. Please set "ReportToManagerEnabled" or "ReportToOriginatorEnabled" to false.

  
  You will need to first set ReportToManagerEnabled to false using this command:
  

  Set-DistributionGroup <Group Email Address> -ReportToManagerEnabled $false

  
  Where <Group Email Address> is replaced with the email address for the affected group
  Then set ReportToOriginatorEnabled to true as above.
  TIP! To quickly set ReportToOriginatorEnabled to true for all groups, run these two commands:
  

  Get-DistributionGroup | Where-Object {$_.ReportToManagerEnabled -eq $True} | Set-DistributionGroup -ReportToManagerEnabled $false
  
  Get-DistributionGroup | Where-Object {$_.ReportToOriginatorEnabled -eq $false} | Set-DistributionGroup -ReportToOriginatorEnabled $true

Exchange Online has a setting that can cause the mail from address to be missing for emails sent to an individual user. This setting is JournalingReportNdrTo and can cause this issue even if your organization hasn't configured any journaling rules. 

The JournalingReportNdrTo setting is intended for specifying a mailbox for Non-Delivery Reports (NDRs) to be delivered when journalling messages fail.

According to Microsoft, "Any mail to JournalingReportNdrTo mailbox will not be journaled, and it will not honor transport and mailbox rules settings. It is recommended to create a dedicated mailbox for the JournalingReportNdrTo setting or set it to an external address."

The Exclaimer Support team find that this setting is commonly configured so that an Administrator is set to receive these journalling NDRs; however, this is against best practices and will lead to mail delivery issues.

To set a dedicated mailbox as the recipient for Journal Report NDR messages:
NOTES: The steps described below should be applied even if message journaling is not enabled; the steps are for both the GUI and PowerShell - please select the method that works best for you: 

To configure the JournalingReportNdrTo setting using the Microsoft Purview portal (GUI):

1. Browse to the Microsoft Purview compliance portal.
   
   
2. Navigate to Solutions > Data lifecycle management >Exchange Legacy.
   
   
3. Click Settings.
   
   
4. Under Send undeliverable journal reports to:, click Replace.
   
   
5. Enter the email address for a dedicated mailbox for receiving journalling NDRs.

To configure the JournalingReportNdrTo setting using PowerShell:

Install Exchange Online PowerShell V2 module:

1. Open the Windows PowerShell and run this command as an Administrator:
   
   Install-Module -Name ExchangeOnlineManagement
2. Confirm that you want to install this PowerShell module.
   NOTE: For additional installation options, see ExchangeOnlineManagement.

Connect to Exchange Online:

• Run this command:
  
  Connect-ExchangeOnline -UserPrincipalName <UPN> -ShowProgress $true
  
  When prompted, enter your password (and the Multi-Factor Authentication verification code if required).

To check the JournalingReportNdrTo setting:

• Run the following command:
  
  Get-transportconfig |fl JournalingReportNdrTo

To configure the JournalingReportNdrTo setting:

• Run the following command: 
  
  set-transportconfig -JournalingReportNdrTo <insert mailbox address>

If you configured Exclaimer Cloud before a specific time, you might find that your out-of-office notification emails (automatic replies) fail to deliver. To resolve this issue, you can do one of the following:

• Option 1 (Recommended): Create a new transport rule in addition to the existing Exclaimer Cloud transport rules already set up. The new rule will ensure that Exclaimer Cloud does not process 'Out of Office' emails. 
  
  
• Option 2: Re-run the connector setup: The Microsoft 365 connector setup will automatically create the Transport Rule. 
  See how you can re-run the Microsoft 365 connector setup. Also, please note that it can take up to a few hours for the changes to come into effect.
  

To create a new Transport rule:
NOTE: The steps described below are for both the GUI and PowerShell; please select the method that works best for you: 

To create a new transport rule in the Exchange Admin center (GUI):

1. Sign in to the Exchange Online admin portal (https://admin.exchange.microsoft.com) as an Administrator.
   
   
2. From the left-hand navigation menu, select Mail flow, then select Rules:
   
   
   
   
3. From the right-hand pane, click the + Add a rule (plus) drop-down and select Create a new rule...
   
   
   
   A new rule window is displayed.
   
   
4. In Name, enter Prevent Out of Office messages being sent to Exclaimer Cloud.
   
   
5. From Apply this rule if... drop-down select The message properties...then select include the message type.
   
   
   
   
6. For select message type, specify Automatic reply.
   
   
7. Click Save.
   
   
8. In Do the following...drop-down, select Modify the message properties...then select set a message header.
   
   
   
   
9. Set the message header to X-ExclaimerHostedSignatures-MessageProcessed.
   
   
10. Now, set the value to true.
    
11. Click Next.
    
    
12. Tick the Activate this rule on option.
    
13. Click Next.
    
    
14. Click Finish to save the changes made.
    
    The new rule will now be displayed in the rules list.
    
    
     
15. Select the new rule, then click Move Up to ensure that the priority is lower than the rule Identify messages to send to Exclaimer Cloud.
    
    
    The rules are now in the correct order:
    
    
    NOTE: It can take up to a few hours for the changes to come into effect.

To create a new transport rule using PowerShell:

Install Exchange Online PowerShell V2 module:

1. Open the Windows PowerShell and run this command as an Administrator:
   
   Install-Module -Name ExchangeOnlineManagement
2. Confirm that you want to install this PowerShell module.
   NOTE: For additional installation options, see ExchangeOnlineManagement.

Connect to Exchange Online:  

• Run this command:
  
  Connect-ExchangeOnline -UserPrincipalName <UPN> -ShowProgress $true
  
  When prompted, enter your password (and the Multi-Factor Authentication verification code if required).

Create the transport rule:

• Run this command: 
  
  New-TransportRule -Name "Prevent Out of Office messages being sent to Exclaimer Cloud" -MessageTypeMatches OOF -enabled $true -SetHeaderName "X-ExclaimerHostedSignatures-MessageProcessed" -SetHeaderValue "true" -Priority 0

NOTE: It can take up to a few hours for the changes to come into effect.