Currently Outlook does not have such an option.
FWIW: Outlook 2010 will have a Conversation Cleanup feature.
--
Robert Sparnaaij [MVP-Outlook]
Coauthor, Configuring Microsoft Outlook 2003
http://www.howto-outlook.com/
Outlook FAQ, HowTo, Downloads, Add-Ins and more
http://www.msoutlook.info/
Real World Questions, Real World Answers
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"Janet" <(E-Mail Removed)> wrote in message
news:4FBAAFF7-AC18-4292-BC34-(E-Mail Removed)...
> There should be an add in or option to only keep the most recent version
> of a
> long involved email thread in your inbox. When I come back from vacation,
> I
> want to have ONE version to read. However, sometimes people add new
> recipients or delete others, and there end up being multiple threads, so I
> have to check them all.
>
> Is there anything out there that does this? I'm not looking for one of
> the
> duplicate programs because they are not exactly duplicates.