I think that this information will be useful to you.
https://support.microsoft.com/en-us/kb/270670
http://social.technet.microsoft.com/Forums/en-US/eb43fb3b-bd62-4421-a8ea-e3e8c6bc6d15/how-to-perform-dbx-extract?forum=itproxpsp
Hi,
I have a user, who through poor management has let their Inbox, Set Items & Deleted Items grow to exceed 2GB. There are also multiple copies of these files.
When trying to delete single messages or multiple messages from these folders, nothing happens.
What should I do now as the user doesn’t want to delete all messages from these files, the remaining would be moved to other appropriate folders.
Thanks in Advance

Chowhound
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