Being curious, too, I checked and found this:

"If you are using Outlook 2003 in a Microsoft Exchange 
environment you have the option to recall e-mail messages that 
you have sent to other Outlook clients in the Exchange 
environment."

http://www.onlinecomputertips.com/office/message_recall.html

I'd have thought that it would only affect addresses in that 
environment. Is this another case of M$ presuming that if you're 
not in their environment you don't exist?

-- Russ

> On Wed, 18 Apr 2007, Helmke,Richard A wrote:
> >  I just saw the aftermath of someone attempting to "unsend" a message to
> > a LISTSERV list and all the bounce back of "message recall failure" back
> > to the list.  What a mess.  I have now added a CONTENT FILTER for the
> > "message recall failure", but now am wondering if there is a way to
> > inhibit this kind of Exchange command being distributed by LISTSERV. Any
> > other things I should be filtering from Exchange?
> 
> I don't keep up with all the "features" of all the mail systems, only the
> ones that cause problems on my lists.  I've never encountered this.  What
> is it, and how is it supposed to work?
> 
> As one really can't "unsend" what has been sent, especially once delivered,
> any more than one can "unsay" what one has said and been heard by others,
> what is this supposed to do?  Delete the item from the recipients email
> inbox?  What if it has alrady been read?  Saved to some other file/folder?
> 
> Douglas Winship    [log in to unmask]

St. Thomas University
http://www.stu.ca/~hunt/