Hi, @York
From your description, I understand that you want to make it possible for a recipient to be able to see which alias received the email directly in the mail client, rather than displaying the primary email address all the time.
Unfortunately, in email clients such as Outlook we don't currently support directly displaying the specific alias email address of the message you received. Recipients will always see the primary email address as a recipient, and there is no built-in feature to display aliases directly in the email client.
However, a common workaround is to create a rule or use a Search Folder to filter and identify emails based on their recipient aliases.
Here are two common alternative solutions:
1.Create a rule
-Click New rule and select “apply rule on messages I receive”.
-Select "Include specific words in recipient addresses".
-Click on "specific words" below, then enter the alias email address, then click "Add" and "OK".
-Click Next, and then choose an action, such as moving the email to a specific folder or displaying a specific alert (depending on your needs).
More information can be found Create custom actions rules in Outlook for Windows - Microsoft Support
2.Use the search folder
Use different specific aliased email addresses as a criterion for categorization.
More information can be found Use Search Folders to find messages or other Outlook items - Microsoft Support
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