Hi @Jerry Silva ,
According to my test, I can open and view the members of distribution group in GAL .However , When I opened the Dynamic Distribution Group in the same way, there was nothing.
In addition, I found the relevant thread for your reference: How to view members of Dynamic Distribution Group via Outlook client? (microsoft.com)
Also, according to this link, you can only view the member list of DDL through the EMS.
Hope this helps you!
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