Using the New Outlook for Mac features in business environments
Hi Darren,
Welcome to the Microsoft Q&A forum.
For the "Attribution of original message" setting in Outlook for Mac, Outlook currently supports custom formatting on a single line only. Therefore, you cannot add multiple lines or apply a multi-line format to this section.
If you have any other questions or concerns, please feel free to share them with me. I would be more than happy to assist you.
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