Hi mark pollard
Please note that our forum is a public platform, and we will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data.
I understand your concern about your email address appearing instead of your display name.To help narrow this down, could you please confirm which Outlook version you are using, such as Outlook on the web, new Outlook, classic Outlook, Mac, or mobile? Also, is this a personal Outlook.com account or a Microsoft 365 work or school account?
If possible, please also confirm whether the email address appears only when you Cc yourself or when other recipients view your messages as well.
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