I don't think what you ask is possible for a variety of reasons. Foremost is that the distribution list is the sender's list and not yours. The message doesn't indicate whether the sender used such a list, but that you were the recipient or one of the recipients. If (like me) the sender uses BCC to send to the distribution list members, you would not be aware that it was a list or that it was sent to others.

You could check if your name was amongst others in the To or CC field, but that wouldn't indicate specifically the use of a distribution list, and you would need a macro script to evaluate the content of the To and CC fields to establish if there was more than one recipient.

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Graham Mayor - MS MVP (Word) (2002-2019)
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