Missing Recipients from Distribution Lists which are Dynamic and/or Hidden (Exchange Servers)

Issue

Sending an individually tracked email using the Graph List Expansion or EWS List Expansion method does not show an accurate list of users.  The users are not counted and do not show up in the campaign stats.  It is possible to send emails to the users directly, without using ContactMonkey.

Reason

Customers may be finding that their recipients are inaccurate when enabling Individual Tracking.  Customers may have already enabled the Graph Utility Account, and are still seeing inaccurate information in certain sending scenarios.  In some scenarios, the combinations of list types being used will determine whether the recipients can be seen due to whether they are supported or not supported by the expansion method chosen.

For more information on how tracking is processed in an Exchange Environment, please visit the following article on List Expansion Methods. 

One or many of the used distribution lists likely have attributes that restrict their ability to be counted due to restrictions by Microsoft on the data developers have through Graph or EWS. 

Sample Scenario

In a sample scenario, if a user is sending using Graph List Expansion, and attempting to send to a Dynamic Exchange Group, the group will not be counted.  
This is because according to the chart below, the Graph API cannot recognize Dynamic Exchange groups.    In this case above the EWS expansion method should be chosen in your ContactMonkey Outlook Add-In Settings.  

In another scenario, users may also encounter Distribution Lists with additional Distribution Lists embedded/nested within them.  The most complicated situation is when those Distribution lists are both hidden and dynamic. 

In this case, the situation becomes more complicated.  Customers cannot choose either Graph Expansion or EWS Expansion.  This is because the Hidden Dynamic Distribution List will not be countable by Graph Expansion.  After all, it is a dynamic distribution list.  It also cannot be accessed by the EWS Expansion Method because it is hidden.

Resolution

Adjust the properties of the Distribution List

Customers can make a couple of choices concerning their distribution lists.  First, they can look to change the properties of the Dynamic Hidden Distribution List so that it is no longer hidden.  In this case, Customers will need to choose EWS Expansion once all lists are no longer hidden.  

Administrators can also look to convert the Dynamic Distribution List into an O365 Dynamic Group or make it a non-dynamic group so customers can continue to use the Graph Expansion method.  

Customers can also seek to add different Distribution Lists that do not have any of these properties to help cover the missing recipients.  

List Management

Customers looking for an alternative option may also look to add ContactMonkey's List Management feature to their services.  We recommend contacting your Customer Success manager if you would like to utilize the List Management feature.