Using Classic Outlook on Windows for personal email, calendar, and contact management
When you click Reply, Outlook uses the sender information contained in the original message. It does not automatically replace the email address with the display name saved in your Contacts.
Unfortunately, there is currently no setting in either Classic Outlook or New Outlook that allows your saved contact’s display name to appear automatically when replying. The name shown in the To field depends on the information provided by the sender’s email account or mail server.
As a workaround, you would need to remove the email address from the To field and manually select the saved contact.
Please keep in mind that this is a community-based support forum. Contributors and moderators, including external Microsoft staff, do not have access to Outlook’s back-end systems and cannot directly change or implement product features. Our role is limited to providing technical guidance based on the currently available functionality.
Please feel free to let me know if you have any further questions.
If the answer is helpful, please click "Yes". If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.