I can't send an email using a distribution list. The distribution lists are showing in my group contacts, but the emails will not go out.

Question

When I look at my contacts and groups in outlook, it shows my2 distribution lists, but if I click on one of them it shows no contacts in the list, but if I click on edit, the contacts are in the distribution lists. When I try to send an email from the distribution lists, they won't go out.

Answer 1

Hi @George Gaspar

I would like to first clarify how these distribution lists were created, as the behavior can differ depending on the type of list.

Are these distribution lists that were created and managed by your Microsoft 365 administrator, or are they lists that were created within Outlook’s People/Contacts section?

The reason I ask is that different types of lists behave differently in Outlook on the web. For example, administrator-managed distribution lists are directory objects and may not appear or behave the same way as personal contact lists. In contrast, personal contact lists are stored in your mailbox and cannot be used as a From address when sending email.

Since the members are visible when you edit the distribution list, this suggests that the underlying membership information is still present. However, Outlook on the web may not be correctly resolving or displaying the members when viewing the list, which can also affect sending behavior.

Regarding the sending issue, when you mention that emails sent from the distribution list do not go out, could you please confirm whether you are attempting to use the distribution list as the From address, or simply sending to the list?

• If you are sending from the distribution list, please let us know whether you receive any error message or non-delivery report (NDR), and share the exact wording if possible. Sending as a distribution list typically requires the appropriate Send As or Send on Behalf permissions.
• If you are sending to the distribution list, any NDR or error details would also help determine whether the list is failing to expand or resolve correctly.

In addition, issues like this can sometimes be caused by a corrupted contact list or an invalid entry, which can prevent the list from displaying or resolving properly.

To help narrow this down further, could you please confirm the following:

• Does the issue occur with both distribution lists or only one?
• If you create a new test distribution list, does it show the same behavior?
• Have you tried Outlook on the web using a different browser or an InPrivate/Incognito window, and does the behavior remain the same?

Please know that while our initial response might not resolve the issue right away, your input is incredibly valuable. With a bit more detail, we’ll work together to find the best solution for you.               

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