Hi Dan McDermott,
Welcome to Microsoft Q&A forum.
I understand what you’re trying to do. In classic Outlook, the Auto-Complete list is not the same as your Contacts folder, so Outlook does not provide a button to load every saved contact into Auto-Complete at once.
Auto-Complete is mainly built from addresses you have previously used when sending email. However, you can still access your saved contacts without typing each address manually:
- Open a new email.
- Select To….
- Choose your Contacts or Address Book.
- Select the recipients you want to add.
If you often email the same group of people, you may also want to create a Contact Group in classic Outlook. That way, you can add the group to an email instead of entering each contact individually.
So, while you can use your contacts from the Address Book, there is no built-in way in classic Outlook to automatically add all contacts into the Auto-Complete list in one step.
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