MAIL FOLDER - DON'T DELETE THIS MESSAGE

[David Banning]

I get the following message in my mailbox from time to time. Is it really
necessary to keep it there? Where does it come from, and why is it 
produced?
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From: Mail System Internal Data <MAILER-DAEMON at 3s1.com>
Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA

This text is part of the internal format of your mail folder, and is not
a real message.  It is created automatically by the mail system software.
If deleted, important folder data will be lost, and it will be re-created
with the data reset to initial values.
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