In new Outlook for Windows, contact lists can only be populated by adding people who are already contacts (i.e., in the Contacts store). There is no supported way in the client to paste a raw list of email addresses directly into a new contact list without those addresses first existing as contacts.
The supported workflows are:
- Create a contact list and add existing contacts
- Go to People.
- Create a New contact list.
- Add names or email addresses that resolve from existing contacts.
- Add contacts first, then add them to a list
- Create contacts (manually or via import, e.g., from a .csv file).
- Then use Add to list or edit the contact list and add those contacts.
Outlook on the web and Outlook.com follow the same model: contact lists are created in a Contacts folder, and people are added by name or email from that store; there is no bulk “paste list of addresses into list” feature documented.
So there is no built‑in workaround that bypasses having the addresses in Contacts first. Any bulk operation must go through creating/importing contacts, then assigning them to a contact list.
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