Ah, ok, No, thats not possible to add a "variable" like that. :)
You can only add a specific string value like your example.
Exchange Online - Add Senders Email Address in Message Header
Stephen Lee
41
Reputation points
Hi Everyone,
When you append a message header in exchange online can you add the sender email address within the header? Any attributes I can add to get it working?
Thanks
Accepted answer
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Andy David - MVP 142.3K Reputation points MVP
2020-09-18T23:20:59.05+00:00