I have preformed a staged migration from Exchange 2007 SP1 to Exchange Online.  I
have made all of my Exchange 2007 users MEUs.  My some 500 user mailboxes
and exchange database is taking up about 450 gigs on my exchange servers hard
drive.  What I want to do is delete all of those old emails within the
user accounts on the exchange 2007 server hopefully freeing up a lot of space.
 What is the best way to go about doing this?  I want to be able to
setup a new exchange server that does not require as much space on my virtual
server. The old exchange server is being used as a email relay and to manage
exchange online user attributes.  

Thanks for the guidance. 

• Edited by Eashton123 Thursday, June 25, 2015 3:09 PM

This doesn't delete my users or render them unmanageable?

Nope not at all, it just creates a new blank database and any mailboxes that were homed to that DB get fresh clean/empty mailboxes and mail just begins to flow again. 

We use this all the time for organizations that have a crashed DB and want to get mail flowing again.  The only difference is we rename the EDB since we want to preserve the contents of that DB for injection into the new EDB via our DigiScope product.

However in your case you say there is no data you want within the EDB, therefore you can just delete it.  However if you are not 100% sure you can always copy the EDB off to an alternate location to preserve for some time and then delete it from its existing location