Dear @Harold DeLauder,
Thank you for posting your question in the Microsoft Q&A forum.
I apologize for any inconvenience you may encounter when using our services/ products. Based on your description:
This behavior may occur when the New Outlook for Windows does not correctly resolve a Contact List into individual recipients when you send the message.
In the meantime, kindly try this workaround step:
- Start a New mail.
- In To, type/select your Contact List name.
- Select the “+” (plus) icon next to the list name to expand it into individual addresses.
- Send again.
If you do not see the “+” option to expand the Contact List, please try recreating the list in People (New Outlook) and test again:
People > New Contact > New contact list > Add members > Send an email to the list (and expand with “+” if it’s available).
I sincerely hope you understand that the initial steps I suggested may not have completely fixed the issue, as there may still be underlying causes that have not yet been identified. I am here to work closely with you, troubleshoot effectively, and explore every possible solution to ensure the best possible outcome.
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