I'm a little confused by your post. If you are saying that you are trying to install the client on a Server it will not work. There is some hacking you can do to make it work, but you should really install the server version on that box.
In the mean time, if the server is sending out thousands of emails, take it off line. Your best bet is going to wipe and rebuild the server.
Sorry and good luck!
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Mens et Manus
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