It depends on their format. You can use this method:
http://www.outlook-tips.net/archives/2004/20041105.htm

Signature
Russ Valentine
[MVP-Outlook]
> OL2003 - I would like to be able to create a distribution list based of
> the multiple email addresses in the To: line on a recently received email.
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>
> Jack
Jack Folliard - 13 Apr 2006 04:58 GMT
thanks
> It depends on their format. You can use this method:
> http://www.outlook-tips.net/archives/2004/20041105.htm
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>>
>> Jack
Hi Jack
You can use a program called Email Address Collector to do this. It can
extract email addresses from your received emails or various other sources
and save them to a distribution list in contacts or to a CSV file. You can
find it here: http://www.emailaddressmanager.com/features.html
> OL2003 - I would like to be able to create a distribution list based of
> the multiple email addresses in the To: line on a recently received email.
[quoted text clipped - 6 lines]
>
> Jack
Jack Folliard - 13 Apr 2006 05:10 GMT
thanks for the info, Don - but I explored the trial version and could not
find a method to create a DL from a received multi-addressed email nor any
reference to distributions lists in the help index/search.
Can you walk me through it a bit?
thanks.
Jack
> Hi Jack
>
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>>
>> Jack